diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 000000000..2c67e2773
Binary files /dev/null and b/.DS_Store differ
diff --git a/00_hello/hello.rb b/00_hello/hello.rb
index 251797306..234606ee4 100644
--- a/00_hello/hello.rb
+++ b/00_hello/hello.rb
@@ -1 +1,7 @@
-#write your code here
+def hello
+   "Hello!"
+end
+
+def greet(name)
+    "Hello, #{name}!"
+end
diff --git a/01_temperature/temperature.rb b/01_temperature/temperature.rb
index 251797306..b6a8c05bd 100644
--- a/01_temperature/temperature.rb
+++ b/01_temperature/temperature.rb
@@ -1 +1,8 @@
 #write your code here
+def ftoc(f)
+    (f-32.0) * (5.0/9.0)
+end
+
+def ctof(c)
+    c * (9.0/5.0) + 32
+end
\ No newline at end of file
diff --git a/02_calculator/calculator.rb b/02_calculator/calculator.rb
index 251797306..6e90abafd 100644
--- a/02_calculator/calculator.rb
+++ b/02_calculator/calculator.rb
@@ -1 +1,30 @@
 #write your code here
+def add(x, y)
+    x + y
+end
+
+def subtract(x,y)
+    x - y
+end
+
+def sum(array)
+    array.inject(0){|total,number| total + number}
+end
+
+
+def multiply(x,y)
+    x * y
+end
+
+def power(x,y)
+    x ** y
+end
+
+
+def factorial(x)
+    if x <= 1
+        1
+    else
+        x * factorial(x-1)
+    end
+end
\ No newline at end of file
diff --git a/02_calculator/calculator_spec.rb b/02_calculator/calculator_spec.rb
index fef7e9d00..3c436b3a4 100644
--- a/02_calculator/calculator_spec.rb
+++ b/02_calculator/calculator_spec.rb
@@ -77,11 +77,11 @@
 # once the above tests pass,
 # write tests and code for the following:
 
-describe "#multiply" do
+describe "multiply" do
 
   it "multiplies two numbers"
+    expect(multiply(2,3)).to eq(6)
 
-  it "multiplies several numbers"
   
 end
 
diff --git a/03_simon_says/simon_says.rb b/03_simon_says/simon_says.rb
index 251797306..7be4052da 100644
--- a/03_simon_says/simon_says.rb
+++ b/03_simon_says/simon_says.rb
@@ -1 +1,35 @@
 #write your code here
+def echo(x)
+    x
+end
+
+def shout(x)
+    x.upcase
+end
+
+def repeat(x, times = 2)
+    ([x] * times).join(" ")
+end
+
+def start_of_word(x , n)
+    x[0 ... n]
+end
+
+def first_word(x)
+    x.split(" ").first
+end
+
+def titleize(s)
+    words = s.split.map do |word|
+        if ["and", "the","over"].include? word
+            word
+        else 
+            word.capitalize
+        end
+    ends
+    words[0].capitalize!
+    words.join(" ")
+    words
+end
+    
+
diff --git a/Gemfile.lock b/Gemfile.lock
index ab1e7db63..5e8aebfc8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,7 +2,7 @@ GEM
   remote: https://rubygems.org/
   specs:
     diff-lcs (1.3)
-    rake (10.5.0)
+    rake (12.3.3)
     rspec (3.5.0)
       rspec-core (~> 3.5.0)
       rspec-expectations (~> 3.5.0)
@@ -21,8 +21,8 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  rake (< 11.0)
+  rake (~> 12.3)
   rspec (~> 3.4)
 
 BUNDLED WITH
-   1.13.6
+   1.17.2