diff --git a/ch09-writing-your-own-methods/ask.rb b/ch09-writing-your-own-methods/ask.rb
index 01716eb35..4092c6765 100644
--- a/ch09-writing-your-own-methods/ask.rb
+++ b/ch09-writing-your-own-methods/ask.rb
@@ -1,3 +1,31 @@
 def ask question
-  # your code here
-end
\ No newline at end of file
+    while true
+        puts question
+        reply = gets.chomp.downcase
+        if (reply == 'yes' || reply == 'no')
+            if reply == 'yes'
+                return true
+            else
+                return false
+            end
+        else
+            puts 'Please answer "yes" or "no".'
+        end
+    end
+end
+
+puts 'Hello, and thank you for...'
+puts
+ask 'Do you like eating tacos?' 
+ask 'Do you like eating burritos?'
+wets_bed = ask 'Do you wet the bed?'
+ask 'Do you like eating chimichangas?'
+ask 'Do you like eating sopapillas?'
+puts 'Just a few more questions...'
+ask 'Do you like drinking horchata?'
+ask 'Do you like eating flautas?'
+puts
+puts 'DEBRIEFING:'
+puts 'Thank you for...'
+puts
+puts wets_bed
\ No newline at end of file
diff --git a/ch09-writing-your-own-methods/old_school_roman_numerals.rb b/ch09-writing-your-own-methods/old_school_roman_numerals.rb
index ca6589f2d..cabbb572b 100644
--- a/ch09-writing-your-own-methods/old_school_roman_numerals.rb
+++ b/ch09-writing-your-own-methods/old_school_roman_numerals.rb
@@ -1,3 +1,51 @@
 def old_roman_numeral num
-  # your code here
-end
\ No newline at end of file
+    
+  if num <= 0
+    return '>0 only please!'
+  end
+  
+  #this will be our roman numeral string:
+  roman_numeral = ''
+  
+  # deal with 1000s
+  thousands = num/1000
+  if thousands > 0
+      roman_numeral = 'M'*thousands
+      num = num - thousands*1000
+  end
+  
+  #deal wih 100s
+  hundreds = num/100
+  if hundreds >= 5
+      roman_numeral = roman_numeral + 'D' + 'C'*(hundreds-5)
+  elsif hundreds > 0
+      roman_numeral = roman_numeral + 'C'*hundreds
+  end
+  num = num - hundreds*100
+      
+  #deal wih 10s
+  tens = num/10
+  if tens >= 5
+      roman_numeral = roman_numeral + 'L' + 'X'*(tens-5)
+  elsif tens > 0
+      roman_numeral = roman_numeral + 'X'*tens
+  end
+  num = num - tens*10
+      
+  #deal wih 1s
+  if num >= 5
+      roman_numeral = roman_numeral + 'V' + 'I'*(num-5)
+  elsif num > 0
+      roman_numeral = roman_numeral + 'I'*num
+  end
+  
+  return roman_numeral
+      
+end
+
+puts 'Translation:'
+puts '3541 is ' + old_roman_numeral(3541)
+puts '0 is '+ old_roman_numeral(0)
+puts '-123 is ' + old_roman_numeral(-123)
+puts '2077 is ' + old_roman_numeral(2077)
+puts '2005 is ' + old_roman_numeral(2005)
\ No newline at end of file
diff --git a/ch09-writing-your-own-methods/roman_numerals.rb b/ch09-writing-your-own-methods/roman_numerals.rb
index 5c93b59ac..a97b2163c 100644
--- a/ch09-writing-your-own-methods/roman_numerals.rb
+++ b/ch09-writing-your-own-methods/roman_numerals.rb
@@ -1,3 +1,61 @@
 def roman_numeral num
-  # your code here
-end
\ No newline at end of file
+  if num <= 0
+    return '>0 only please!'
+  end
+  
+  #this will be our roman numeral string:
+  roman_numeral = ''
+  
+  # deal with 1000s
+  thousands = num/1000
+  if thousands > 0
+      roman_numeral = 'M'*thousands
+      num = num - thousands*1000
+  end
+  
+  #deal wih 100s
+  hundreds = num/100
+  if hundreds == 9
+      roman_numeral = roman_numeral + 'CM'
+  elsif hundreds >= 5
+      roman_numeral = roman_numeral + 'D' + 'C'*(hundreds-5)
+  elsif hundreds == 4
+      roman_numeral = roman_numeral + 'CD'
+  elsif hundreds > 0
+      roman_numeral = roman_numeral + 'C'*hundreds
+  end
+  num = num - hundreds*100
+      
+  #deal wih 10s
+  tens = num/10
+  if tens == 9
+      roman_numeral = roman_numeral + 'XC'
+  elsif tens >= 5
+      roman_numeral = roman_numeral + 'L' + 'X'*(tens-5)
+  elsif tens == 4
+      roman_numeral = roman_numeral + 'XL'
+  elsif tens > 0
+      roman_numeral = roman_numeral + 'X'*tens
+  end
+  num = num - tens*10
+      
+  #deal wih 1s
+  if num == 9
+      roman_numeral = roman_numeral + 'IX'
+  elsif num >= 5
+      roman_numeral = roman_numeral + 'V' + 'I'*(num-5)
+  elsif num == 4
+      roman_numeral = roman_numeral + 'IV'
+  elsif num > 0
+      roman_numeral = roman_numeral + 'I'*num
+  end
+  
+  return roman_numeral
+end
+
+puts 'Translation:'
+puts '3541 is ' + roman_numeral(3541)
+puts '0 is '+ roman_numeral(0)
+puts '-123 is ' + roman_numeral(-123)
+puts '2077 is ' + roman_numeral(2077)
+puts '2005 is ' + roman_numeral(2005)
\ No newline at end of file
diff --git a/ch10-nothing-new/aga.jpg b/ch10-nothing-new/aga.jpg
new file mode 100644
index 000000000..c6ca9968d
Binary files /dev/null and b/ch10-nothing-new/aga.jpg differ
diff --git a/ch10-nothing-new/dictionary_sort.rb b/ch10-nothing-new/dictionary_sort.rb
index c9893d0fd..cf9825267 100644
--- a/ch10-nothing-new/dictionary_sort.rb
+++ b/ch10-nothing-new/dictionary_sort.rb
@@ -1,3 +1,31 @@
 def dictionary_sort arr
-  # your code here
-end
\ No newline at end of file
+  recursive_sort arr, []
+end
+
+#the method that actually does sorting
+def recursive_sort unsorted_array, sorted_array
+    j = 1
+    
+    smallest_index = 0
+    
+    until unsorted_array.length == 0
+
+        # find smallest in unsorted_array
+        while j < unsorted_array.length
+            smallest_index = j if unsorted_array[j].to_s.downcase < unsorted_array[smallest_index].to_s.downcase
+            j += 1
+        end
+        
+        # move it from the unsorted array to the end of already_sorted
+        sorted_array << unsorted_array[smallest_index]
+        unsorted_array.delete_at(smallest_index)
+        
+        # find next smallest with recursive call
+        recursive_sort unsorted_array, sorted_array
+    end
+    
+    return sorted_array
+end
+
+puts dictionary_sort ["avada", "Kedavra", "black", "SirIUs", "harry"]
+puts dictionary_sort ["A","feel", "can", "like", "can","singing"]
\ No newline at end of file
diff --git a/ch10-nothing-new/english_number.rb b/ch10-nothing-new/english_number.rb
index c0129bc4e..ab80a51e3 100644
--- a/ch10-nothing-new/english_number.rb
+++ b/ch10-nothing-new/english_number.rb
@@ -1,3 +1,109 @@
 def english_number number
-  # your code here
+    
+  if number < 0
+    return 'Please enter a number that isn\'t negative.'
+  end
+  
+  if number == 0
+    return 'zero'
+  end
+
+  num_string = '' # This is the string we will return.
+  
+  ones_place = ['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine']
+  tens_place = ['ten', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety']
+  teenagers = ['eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen']
+  higher_powers = ['thousand','million', 'billion', 'trillion', 'quadrillion', 'quintillion', 'sextillion', 'septillion', 
+  'octillion', 'nonillion', 'decillion', 'undecillion', 'duodecillion', 'tredecillion', 'quattuordecillion', 'quindecillion',
+  'sedecillion', 'septendecillion', 'octodecillion', 'novendecillion', 'vigintillion']
+  
+    # "left" is how much of the number we still have left to write out.
+    # "write" is the part we are writing out right now.
+  left = number
+  write = 0
+  
+  #deal with thousands up to vigintillions
+  #start from vigintillion and go down to find the lowest power when write is not 0
+  power = 63
+  i = 20
+  
+  until power == 0
+    ten_power = 10**power
+    write = left/ten_power
+    left = left - write*ten_power
+    if write > 0
+      illions = english_number write
+      num_string = num_string + illions + ' ' + higher_powers[i]
+      if left > 0
+        # Add space between thousands and hundreds
+        num_string = num_string + ' '
+      end
+    end
+    power -= 3
+    i -= 1
+  end
+  
+  #deal with hundreds
+  write = left/100 # How many hundreds left?
+  left = left - write*100 # Subtract off those hundreds.
+  if write > 0
+     # Now here's the recursion:
+     hundreds = english_number write
+     num_string = num_string + hundreds + ' hundred'
+     if left > 0
+       # So we don't write 'two hundredfifty-one'...
+       num_string = num_string + ' '
+     end
+  end
+
+  #deal with tens
+  write = left/10 
+  left = left - write*10
+  if write > 0
+    #teenagers
+    if ((write == 1) and (left > 0))
+      num_string = num_string + teenagers[left-1]
+      # The "-1" is because teenagers[3] is 'fourteen', not 'thirteen'.
+      left = 0
+    else
+      num_string = num_string + tens_place[write-1]
+      # The "-1" is because tens_place[3] is 'forty', not 'thirty'.
+    end
+    if left > 0
+      # Add space between tens and ones
+      num_string = num_string + '-'
+    end
+  end
+  
+  #deal with ones
+  write = left 
+  left = 0
+  if write > 0
+    num_string = num_string + ones_place[write-1]
+    # The "-1" is because ones_place[3] is 'four', not 'three'.
+  end
+  
+  # TA DA!
+  num_string
+  
 end
+
+
+puts english_number( 0)
+puts english_number( 9)
+puts english_number( 10)
+puts english_number( 11)
+puts english_number( 17)
+puts english_number( 32)
+puts english_number( 88)
+puts english_number( 99)
+puts english_number(100)
+puts english_number(101)
+puts english_number(234)
+puts english_number(3211)
+puts english_number(10000)
+puts english_number(999999)
+puts english_number(1100458)
+puts english_number(1000000000000)
+puts english_number(10**63 + 10**60 + 10**24 + 10*6 + 1215)
+
diff --git a/ch10-nothing-new/jacqui.jpg b/ch10-nothing-new/jacqui.jpg
new file mode 100644
index 000000000..62ed2dc64
Binary files /dev/null and b/ch10-nothing-new/jacqui.jpg differ
diff --git a/ch10-nothing-new/ninety_nine_bottles_of_beer.rb b/ch10-nothing-new/ninety_nine_bottles_of_beer.rb
index 801de24bd..0cadc5658 100644
--- a/ch10-nothing-new/ninety_nine_bottles_of_beer.rb
+++ b/ch10-nothing-new/ninety_nine_bottles_of_beer.rb
@@ -1 +1,99 @@
-# your code here
\ No newline at end of file
+def english_number number
+    
+  if number < 0
+    return 'Please enter a number that isn\'t negative.'
+  end
+  
+  if number == 0
+    return 'zero'
+  end
+
+  num_string = '' # This is the string we will return.
+  
+  ones_place = ['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine']
+  tens_place = ['ten', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety']
+  teenagers = ['eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen']
+  higher_powers = ['thousand','million', 'billion', 'trillion', 'quadrillion', 'quintillion', 'sextillion', 'septillion', 
+  'octillion', 'nonillion', 'decillion', 'undecillion', 'duodecillion', 'tredecillion', 'quattuordecillion', 'quindecillion',
+  'sedecillion', 'septendecillion', 'octodecillion', 'novendecillion', 'vigintillion']
+  
+    # "left" is how much of the number we still have left to write out.
+    # "write" is the part we are writing out right now.
+  left = number
+  write = 0
+  
+  #deal with thousands up to vigintillions
+  #start from vigintillion and go down to find the lowest power when write is not 0
+  power = 63
+  i = 20
+  
+  until power == 0
+    ten_power = 10**power
+    write = left/ten_power
+    left = left - write*ten_power
+    if write > 0
+      illions = english_number write
+      num_string = num_string + illions + ' ' + higher_powers[i]
+      if left > 0
+        # Add space between thousands and hundreds
+        num_string = num_string + ' '
+      end
+    end
+    power -= 3
+    i -= 1
+  end
+  
+  #deal with hundreds
+  write = left/100 # How many hundreds left?
+  left = left - write*100 # Subtract off those hundreds.
+  if write > 0
+     # Now here's the recursion:
+     hundreds = english_number write
+     num_string = num_string + hundreds + ' hundred'
+     if left > 0
+       # So we don't write 'two hundredfifty-one'...
+       num_string = num_string + ' '
+     end
+  end
+
+  #deal with tens
+  write = left/10 
+  left = left - write*10
+  if write > 0
+    #teenagers
+    if ((write == 1) and (left > 0))
+      num_string = num_string + teenagers[left-1]
+      # The "-1" is because teenagers[3] is 'fourteen', not 'thirteen'.
+      left = 0
+    else
+      num_string = num_string + tens_place[write-1]
+      # The "-1" is because tens_place[3] is 'forty', not 'thirty'.
+    end
+    if left > 0
+      # Add space between tens and ones
+      num_string = num_string + '-'
+    end
+  end
+  
+  #deal with ones
+  write = left 
+  left = 0
+  if write > 0
+    num_string = num_string + ones_place[write-1]
+    # The "-1" is because ones_place[3] is 'four', not 'three'.
+  end
+  
+  # TA DA!
+  num_string
+  
+end
+
+def beer_song number
+  while number > 0
+    puts english_number(number).capitalize + " bottles of beer on the wall, " + english_number(number) +  " bottles of beer."
+    puts "Take one down and pass it around, " + english_number(number-1) + " bottles of beer on the wall."
+    number -= 1
+  end
+end
+
+beer_song 9999
\ No newline at end of file
diff --git a/ch10-nothing-new/shuffle.rb b/ch10-nothing-new/shuffle.rb
index a486ad94c..615f357cc 100644
--- a/ch10-nothing-new/shuffle.rb
+++ b/ch10-nothing-new/shuffle.rb
@@ -1,3 +1,29 @@
+=begin
+Defining perfect shuffle as one where no card happens after the same card it did before.
+Implementation here inspired by the "faro in-shuffle"
+=end
+
 def shuffle arr
-  # your code here
-end
\ No newline at end of file
+  #split the array in two
+  left, right = arr.each_slice((arr.size/2.0).round).to_a
+  
+  #generate new array where the two arrays intertwine
+  i = 0
+  shuffled = []
+  while i < right.length
+    shuffled << left[i]
+    shuffled << right[i]
+    i += 1
+  end
+  shuffled << left[i] if i < left.length # for case when arr.length is odd
+  
+  #move the first element to the end
+  shuffled << shuffled[0]
+  shuffled.delete_at(0)
+  
+  return shuffled
+  
+end
+
+puts shuffle([1,2,3,4,5]).to_s
+puts shuffle([10,20,30,40]).to_s
\ No newline at end of file
diff --git a/ch10-nothing-new/sort.rb b/ch10-nothing-new/sort.rb
index 44c6deb58..8d90719f3 100644
--- a/ch10-nothing-new/sort.rb
+++ b/ch10-nothing-new/sort.rb
@@ -1,3 +1,32 @@
 def sort arr
-  # your code here
-end
\ No newline at end of file
+# wrapper method; pass given array for sorting, along with an empty array
+  recursive_sort arr, []
+end
+
+#the method that actually does sorting
+def recursive_sort unsorted_array, sorted_array
+    j = 1
+    
+    smallest_index = 0
+    
+    until unsorted_array.length == 0
+        # find smallest in unsorted_array
+        while j < unsorted_array.length
+            smallest_index = j if unsorted_array[j] < unsorted_array[smallest_index]
+            j += 1
+        end
+        
+        # move it from the unsorted array to the end of already_sorted
+        sorted_array << unsorted_array[smallest_index]
+        unsorted_array.delete_at(smallest_index)
+        
+        # find next smallest with recursive call
+        recursive_sort unsorted_array, sorted_array
+    end
+    
+    return sorted_array
+end
+
+puts sort ["avada", "kedavra", "black", "sirius", "harry"]
+puts sort ["a","feel", "can", "like", "can","singing"]
+
diff --git a/ch10-nothing-new/tom.jpg b/ch10-nothing-new/tom.jpg
new file mode 100644
index 000000000..e69de29bb
diff --git a/ch11-reading-and-writing/build_a_better_playlist.rb b/ch11-reading-and-writing/build_a_better_playlist.rb
index 3b31bd241..03c6aed01 100644
--- a/ch11-reading-and-writing/build_a_better_playlist.rb
+++ b/ch11-reading-and-writing/build_a_better_playlist.rb
@@ -1,3 +1,20 @@
 def music_shuffle filenames
-  # your code here
+  return filenames.shuffle!
 end
+
+# search for music files in current directory
+songs = Dir['*.mp3']
+
+#create the playlist 
+filename = 'playlist.m3u'
+
+songs = music_shuffle songs
+
+songs_string = ''
+songs.each do |song|
+    songs_string << song << "\n"
+end
+
+File.open filename, 'w' do |f|
+    f.write songs_string
+end
\ No newline at end of file
diff --git a/ch11-reading-and-writing/build_your_own_playlist.rb b/ch11-reading-and-writing/build_your_own_playlist.rb
index 801de24bd..913b96ebc 100644
--- a/ch11-reading-and-writing/build_your_own_playlist.rb
+++ b/ch11-reading-and-writing/build_your_own_playlist.rb
@@ -1 +1,16 @@
-# your code here
\ No newline at end of file
+# search for music files in current directory
+songs = Dir['*.mp3']
+
+#create the playlist 
+filename = 'playlist.m3u'
+
+songs.shuffle!
+
+songs_string = ''
+songs.each do |song|
+    songs_string << song << "\n"
+end
+
+File.open filename, 'w' do |f|
+    f.write songs_string
+end
diff --git a/ch11-reading-and-writing/playlist.m3u b/ch11-reading-and-writing/playlist.m3u
new file mode 100644
index 000000000..7f281447e
--- /dev/null
+++ b/ch11-reading-and-writing/playlist.m3u
@@ -0,0 +1,4 @@
+song2.mp3
+song.mp3
+song3.mp3
+song4.mp3
diff --git a/ch11-reading-and-writing/safer_picture_downloading.rb b/ch11-reading-and-writing/safer_picture_downloading.rb
index 801de24bd..12801272c 100644
--- a/ch11-reading-and-writing/safer_picture_downloading.rb
+++ b/ch11-reading-and-writing/safer_picture_downloading.rb
@@ -1 +1,28 @@
-# your code here
\ No newline at end of file
+pic_names = Dir['**/*.{JPG,jpg}']
+puts 'What would you like to call this batch?'
+batch_name = gets.chomp
+puts
+print "Downloading #{pic_names.length} files: "
+
+pic_number = 1
+pic_names.each do |name|
+    print '.' # "progress bar".
+    
+    new_name = if pic_number < 10
+    "#{batch_name}0#{pic_number}.jpg"
+    else
+    "#{batch_name}#{pic_number}.jpg"
+    end
+
+    if File.exist?(new_name)
+        puts "File already exists"
+        exit
+    else
+        File.rename name, new_name
+    end
+
+    pic_number = pic_number + 1
+end
+
+puts
+puts 'Done!'
\ No newline at end of file
diff --git a/ch11-reading-and-writing/song.mp3 b/ch11-reading-and-writing/song.mp3
new file mode 100644
index 000000000..e69de29bb
diff --git a/ch11-reading-and-writing/song2.mp3 b/ch11-reading-and-writing/song2.mp3
new file mode 100644
index 000000000..e69de29bb
diff --git a/ch11-reading-and-writing/song3.mp3 b/ch11-reading-and-writing/song3.mp3
new file mode 100644
index 000000000..e69de29bb
diff --git a/ch11-reading-and-writing/song4.mp3 b/ch11-reading-and-writing/song4.mp3
new file mode 100644
index 000000000..e69de29bb
diff --git a/ch12-new-classes-of-objects/birthday_helper.rb b/ch12-new-classes-of-objects/birthday_helper.rb
index 801de24bd..d61bb4f84 100644
--- a/ch12-new-classes-of-objects/birthday_helper.rb
+++ b/ch12-new-classes-of-objects/birthday_helper.rb
@@ -1 +1,32 @@
-# your code here
\ No newline at end of file
+#read in names and birth dates from file
+read_string = File.read 'dob'
+
+#split by newline to obtain seperate people -> though could have actually also just used each_line on the read_string maybe
+list = read_string.split("\n")
+
+hash_list = Hash.new
+
+#convert to hashes
+list.each do |person|
+    data = person.split(',',2) #returns array of 2 strings, split by first occurence of ,
+    hash_list[data[0]] = data[1].lstrip!
+end
+
+#Time for user interaction:
+puts "Name please"
+name = gets.chomp
+
+if hash_list[name] == nil
+    puts "sorry, not got them on me list"
+    exit
+end
+
+birthday_month, birthday_day = hash_list[name].split(',')[0].split
+birthday_year = hash_list[name].split(',')[1]
+
+year = '2016'
+year = '2017' if Time.new > Time.gm(year, birthday_month, birthday_day)
+
+age = (Time.gm(year, birthday_month, birthday_day) - Time.gm(birthday_year, birthday_month, birthday_day)) / (60*60*24*365)
+
+puts "#{name}'s next birthday is #{birthday_day} #{birthday_month} #{year}. He will be #{age.round} years old."
diff --git a/ch12-new-classes-of-objects/dob b/ch12-new-classes-of-objects/dob
new file mode 100644
index 000000000..e5115be6a
--- /dev/null
+++ b/ch12-new-classes-of-objects/dob
@@ -0,0 +1,8 @@
+Christopher Alexander, Oct 4, 1936
+Christopher Lambert, Mar 29, 1957
+Christopher Lee, May 27, 1922
+Christopher Lloyd, Oct 22, 1938
+Christopher Pine, Aug 3, 1976
+Christopher Plummer, Dec 13, 1927
+Christopher Walken, Mar 31, 1943
+The King of Spain, Jan 5, 1938
\ No newline at end of file
diff --git a/ch12-new-classes-of-objects/happy_birthday.rb b/ch12-new-classes-of-objects/happy_birthday.rb
index 801de24bd..f91694852 100644
--- a/ch12-new-classes-of-objects/happy_birthday.rb
+++ b/ch12-new-classes-of-objects/happy_birthday.rb
@@ -1 +1,16 @@
-# your code here
\ No newline at end of file
+=begin
+Ask what year a person was born in, then the month,
+and then the day. Figure out how old they are, and give them a big SPANK!
+for each birthday they have had.
+=end
+
+puts "what year were you born?"
+year = gets.chomp
+puts "what month?"
+month = gets.chomp
+puts "what day?"
+day = gets.chomp
+
+age = Time.new - Time.local(year,month,day) #gives age in seconds... convert to years:
+age = age/(60*60*24*365)
+puts "SPANK!\n"*age.round
diff --git a/ch12-new-classes-of-objects/one_billion_seconds.rb b/ch12-new-classes-of-objects/one_billion_seconds.rb
index 801de24bd..38c4dc695 100644
--- a/ch12-new-classes-of-objects/one_billion_seconds.rb
+++ b/ch12-new-classes-of-objects/one_billion_seconds.rb
@@ -1 +1,4 @@
-# your code here
\ No newline at end of file
+born = Time.local(1991, 7, 9)
+
+puts "was born on: " + born.to_s
+puts "will be 1 billion seconds old on: #{born + 10**9}"
\ No newline at end of file
diff --git a/ch12-new-classes-of-objects/party_like_its_roman_to_integer_mcmxcix.rb b/ch12-new-classes-of-objects/party_like_its_roman_to_integer_mcmxcix.rb
index 037b6cb09..706b331ff 100644
--- a/ch12-new-classes-of-objects/party_like_its_roman_to_integer_mcmxcix.rb
+++ b/ch12-new-classes-of-objects/party_like_its_roman_to_integer_mcmxcix.rb
@@ -1,3 +1,82 @@
 def roman_to_integer roman
-  # your code here
-end
\ No newline at end of file
+  
+  # only strings with letters I, V, X, L, C, D, M allowed
+  if roman =~ /[^ivxlcdm]/i
+    puts "Not very Roman of you..."
+    exit
+  end
+  
+  #make my life easier, remove case
+  roman.downcase!
+  
+  #will store the final number
+  number = 0
+  
+  while roman.length > 0
+      #let's do it letter by letter
+      if roman[0] == 'm'
+          number = number + 1000
+          roman.slice!(/m/)
+      elsif roman[0] == 'd'
+          number = number + 500
+          roman.slice!(/d/)
+      elsif roman[0] == 'c'
+          if roman[1] == 'm'
+            number = number + 900
+            roman.slice!(/cm/)
+          elsif roman[1] == 'd'
+            number = number + 400
+            roman.slice!(/cd/)
+          else 
+            number = number + 100
+            roman.slice!(/c/)
+          end
+      elsif roman[0] == 'l'
+          number = number + 50
+          roman.slice!(/l/)
+      elsif roman[0] == 'x'
+          if roman[1] == 'c'
+            number = number + 90
+            roman.slice!(/xc/)
+          elsif roman[1] == 'l'
+            number = number + 40
+            roman.slice!(/xl/)
+          else 
+            number = number + 10
+            roman.slice!(/x/)
+          end
+      elsif roman[0] == 'v'
+          number = number + 5
+          roman.slice!(/v/)
+      elsif roman[0] == 'i'
+          if roman[1] == 'x'
+            number = number + 9
+            roman.slice!(/ix/)
+          elsif roman[1] == 'v'
+            number = number + 4
+            roman.slice!(/iv/)
+          else 
+            number = number + 1
+            roman.slice!(/i/)
+          end
+      end
+
+  end
+  
+  return number
+  
+end
+
+puts roman_to_integer 'i'         #1
+puts roman_to_integer 'iiI'       #3
+puts roman_to_integer 'Iv'        #4
+puts roman_to_integer 'V'         #5
+puts roman_to_integer 'VIII'      #8
+puts roman_to_integer 'XXVI'      #26
+puts roman_to_integer 'LIII'      #53
+puts roman_to_integer 'CXCIX'     #199
+puts roman_to_integer 'DCLXXXII'  #682
+puts roman_to_integer 'MMCMXLI'   #2941
+puts roman_to_integer 'MMMX'      #3010
+puts roman_to_integer 'mcmxcix'   #1999
+puts roman_to_integer 'CCCLXV'    #365
\ No newline at end of file
diff --git a/ch13-creating-new-classes/extend_built_in_classes.rb b/ch13-creating-new-classes/extend_built_in_classes.rb
index c3e793933..9116be46b 100644
--- a/ch13-creating-new-classes/extend_built_in_classes.rb
+++ b/ch13-creating-new-classes/extend_built_in_classes.rb
@@ -1,3 +1,61 @@
 class Integer
-  # your code here
-end
\ No newline at end of file
+    
+  def factorial
+    return 'You can\'t take the factorial of a negative number!' if self < 0
+    return 1 if self <= 1
+    self * (self-1).factorial
+  end
+  
+  def to_roman
+      
+    num = self
+    
+      if num <= 0
+        return '>0 only please!'
+      end
+      
+      #this will be our roman numeral string:
+      roman_numeral = ''
+      
+      # deal with 1000s
+      thousands = num/1000
+      if thousands > 0
+          roman_numeral = 'M'*thousands
+          num = num - thousands*1000
+      end
+      
+      #deal wih 100s
+      hundreds = num/100
+      if hundreds >= 5
+          roman_numeral = roman_numeral + 'D' + 'C'*(hundreds-5)
+      elsif hundreds > 0
+          roman_numeral = roman_numeral + 'C'*hundreds
+      end
+      num = num - hundreds*100
+          
+      #deal wih 10s
+      tens = num/10
+      if tens >= 5
+          roman_numeral = roman_numeral + 'L' + 'X'*(tens-5)
+      elsif tens > 0
+          roman_numeral = roman_numeral + 'X'*tens
+      end
+      num = num - tens*10
+          
+      #deal wih 1s
+      if num >= 5
+          roman_numeral = roman_numeral + 'V' + 'I'*(num-5)
+      elsif num > 0
+          roman_numeral = roman_numeral + 'I'*num
+      end
+      
+      return roman_numeral
+      
+  end
+  
+end
+
+puts 3.factorial
+puts 30.factorial
+puts 4.to_roman
+puts 3567.to_roman
diff --git a/ch13-creating-new-classes/interactive_baby_dragon.rb b/ch13-creating-new-classes/interactive_baby_dragon.rb
index 801de24bd..7dfe9711a 100644
--- a/ch13-creating-new-classes/interactive_baby_dragon.rb
+++ b/ch13-creating-new-classes/interactive_baby_dragon.rb
@@ -1 +1,126 @@
-# your code here
\ No newline at end of file
+class Dragon
+    def initialize name
+        @name = name
+        @asleep = false
+        @stuff_in_belly = 10 # He's full.
+        @stuff_in_intestine = 0 # He doesn't need to go.
+        puts "#{@name} is born."
+    end
+    
+    def feed
+        puts "You feed #{@name}."
+        @stuff_in_belly = 10
+        passage_of_time
+    end
+    
+    def walk
+        puts "You walk #{@name}."
+        @stuff_in_intestine = 0
+        passage_of_time
+    end
+        
+    def put_to_bed
+        puts "You put #{@name} to bed."
+        @asleep = true
+        3.times do
+            if @asleep
+            passage_of_time
+            end
+            if @asleep
+            puts "#{@name} snores, filling the room with smoke."
+            end
+        end
+        if @asleep
+            @asleep = false
+            puts "#{@name} wakes up slowly."
+        end
+    end
+    
+    def toss
+        puts "You toss #{@name} up into the air."
+        puts 'He giggles, which singes your eyebrows.'
+        passage_of_time
+    end
+    
+    def rock
+        puts "You rock #{@name} gently."
+        @asleep = true
+        puts 'He briefly dozes off...'
+        passage_of_time
+        if @asleep
+            @asleep = false
+            puts '...but wakes when you stop.'
+        end
+    end
+    
+    def interact
+        puts "What will you do, mommy?"
+        
+        action = gets.chomp.downcase
+        
+        case action
+        when 'feed'
+            self.feed
+        when 'walk'
+            self.walk
+        when 'put to bed'
+            self.put_to_bed
+        when 'toss'
+            self.toss
+        when 'rock'
+            self.rock
+        else
+            puts "You can't do THAT!"
+        end
+        
+    end
+        
+    
+    private
+    
+    def hungry?
+        @stuff_in_belly <= 2
+    end
+    
+    def poopy?
+        @stuff_in_intestine >= 8
+    end
+    
+    def passage_of_time
+        if @stuff_in_belly > 0
+            # Move food from belly to intestine.
+            @stuff_in_belly = @stuff_in_belly - 1
+            @stuff_in_intestine = @stuff_in_intestine + 1
+        else # Our dragon is starving!
+            if @asleep
+                @asleep = false
+                puts 'He wakes up suddenly!'
+            end
+            puts "#{@name} is starving! In desperation, he ate YOU!"
+            exit # This quits the program.
+        end
+        if @stuff_in_intestine >= 10
+            @stuff_in_intestine = 0
+            puts "Whoops! #{@name} had an accident..."
+        end
+        if hungry?
+            if @asleep
+                @asleep = false
+                puts 'He wakes up suddenly!'
+            end
+            puts "#{@name}'s stomach grumbles..."
+        end
+        if poopy?
+            if @asleep
+                @asleep = false
+                puts 'He wakes up suddenly!'
+            end
+            puts "#{@name} does the potty dance..."
+        end
+    end
+end
+
+pet = Dragon.new("Basia")
+10.times do
+    pet.interact
+end
\ No newline at end of file
diff --git a/ch13-creating-new-classes/orange_tree.rb b/ch13-creating-new-classes/orange_tree.rb
index 025d08907..a46e4f50b 100644
--- a/ch13-creating-new-classes/orange_tree.rb
+++ b/ch13-creating-new-classes/orange_tree.rb
@@ -7,5 +7,73 @@
 
 
 class OrangeTree
-  # your code here
+  def initialize
+      @h = 0
+      @age = 0
+      @orange_count = 0
+  end
+  
+  def one_year_passes
+      @age +=1
+      @orange_count = 0 #just to make sure all oranges fell off
+      if @age > 25
+          death
+      else
+          grow
+          if @age > 5
+              make_fruit
+          end
+          "This year your tree grew to #{@h.round(1)}m tall, and produced #{@orange_count.round} oranges."
+      end
+  end
+  
+  def count_the_oranges
+      if @age > 25
+        'A dead tree has no oranges. :('
+      else
+        @orange_count.round
+      end
+  end
+  
+  def height
+      if @age > 25
+          'A dead tree is not very tall. :('
+      else
+        @h.round(1)
+      end
+  end
+  
+  def pick_an_orange
+      return 'A dead tree has nothing to pick. :(' if @age > 25
+      if @orange_count > 0
+        @orange_count -= 1
+        'Mmmmmmmmm. Delicious.'
+      else
+        'No oranges. Sadness. :('
+      end
+  end
+  
+  private
+  
+  def grow
+      @h += 0.4
+  end
+  
+  def death
+      if @age == 26
+        'Oh, no! The tree is too old, and has died. :('
+      else
+        'A year later, the tree is still dead. :('
+      end
+  end
+  
+  def make_fruit
+      @orange_count = @h * 15 - 25
+  end
+      
+end
+
+tree = OrangeTree.new
+28.times do
+      puts tree.one_year_passes
 end
diff --git a/ch14-blocks-and-procs/better_program_logger.rb b/ch14-blocks-and-procs/better_program_logger.rb
index 0e2e18d57..56dba0336 100644
--- a/ch14-blocks-and-procs/better_program_logger.rb
+++ b/ch14-blocks-and-procs/better_program_logger.rb
@@ -1,3 +1,22 @@
-def log desc, &block
-  # your code here
+$level = 0
+
+def better_log desc, &block
+ puts "#{' '*$level}Beginning \"#{desc}\"..."
+ $level += 1
+ result = block.call
+ $level -= 1
+ puts "#{' '*$level}...\"#{desc}\" finished, returning: #{result}"
+end
+
+better_log 'outer block' do 
+    better_log 'some little block' do
+        better_log 'tiny block' do
+            10+11
+        end
+        3+2
+    end
+    better_log 'yet another block' do
+        'I like Thai food!'
+    end
+    2>3
 end
\ No newline at end of file
diff --git a/ch14-blocks-and-procs/even_better_profiling.rb b/ch14-blocks-and-procs/even_better_profiling.rb
index b01b78fd8..e191b7051 100644
--- a/ch14-blocks-and-procs/even_better_profiling.rb
+++ b/ch14-blocks-and-procs/even_better_profiling.rb
@@ -1,3 +1,28 @@
+$PROFILING_ON = true
+
 def profile block_description, &block
-  # your code here
+  if $PROFILING_ON
+    start_time = Time.new
+    block.call
+    duration = Time.new - start_time
+    puts "#{block_description}: #{duration} seconds"
+  else
+      block.call
+  end
+end
+
+profile '25000 doublings' do
+  number = 1
+  25000.times do
+    number = number + number
+  end
+  puts "#{number.to_s.length} digits"
+# That's the number of digits in this HUGE number.
+end
+
+profile 'count to a million' do
+  number = 0
+  1000000.times do
+    number = number + 1
+  end
 end
\ No newline at end of file
diff --git a/ch14-blocks-and-procs/grandfather_clock.rb b/ch14-blocks-and-procs/grandfather_clock.rb
index 916f6d354..82ff6a1ee 100644
--- a/ch14-blocks-and-procs/grandfather_clock.rb
+++ b/ch14-blocks-and-procs/grandfather_clock.rb
@@ -1,3 +1,11 @@
 def grandfather_clock &block
-  # your code here
+  hours = Time.new.hour
+  hours -= 12 if hours > 12
+  hours.times do
+      block.call
+  end
+end
+
+grandfather_clock do
+    puts 'DONG!'
 end
\ No newline at end of file
diff --git a/ch14-blocks-and-procs/program_logger.rb b/ch14-blocks-and-procs/program_logger.rb
index 0e2e18d57..5fd122e3a 100644
--- a/ch14-blocks-and-procs/program_logger.rb
+++ b/ch14-blocks-and-procs/program_logger.rb
@@ -1,3 +1,14 @@
-def log desc, &block
-  # your code here
+def program_log desc, &block
+ puts "Beginning \"#{desc}\"..."
+ puts "...\"#{desc}\" finished, returning: #{block.call}"
+end
+
+program_log 'outer block' do 
+    program_log 'some little block' do
+        3+2
+    end
+    program_log 'yet another block' do
+        'I like Thai food!'
+    end
+    2>3
 end
\ No newline at end of file