diff --git a/csharp-fundamentals-control-flow.Main/Core.cs b/csharp-fundamentals-control-flow.Main/Core.cs
index 9fe1a9d..770a272 100644
--- a/csharp-fundamentals-control-flow.Main/Core.cs
+++ b/csharp-fundamentals-control-flow.Main/Core.cs
@@ -48,61 +48,84 @@ public string sayGoodMorning(bool isMorning)
         // Change the returned value in the method below to your answer. It is case-sensitive.
         public string one()
         {
-            return "";
+            return "Good day!";
         }
 
         //TODO: 2. What will the output be if I run sayGoodMorning(true)?
         // Change the returned value in the method below to your answer. It is case-sensitive.
         public string two()
         {
-            return "";
+            return "Good morning!";
         }
 
         //TODO: 3. What will the output be if I run sayGoodMorning("Hello" == "Hello")?
         // Change the returned value in the method below to your answer. It is case-sensitive.
         public string three()
         {
-            return "";
+            return "Good morning!";
         }
 
         //TODO: 4. What will the output be if I run sayGoodMorning("A word" != "Another word")
         public string four()
         {
-            return "";
+            return "Good morning!";
         }
 
         // 5. What will the output be if I run sayGoodMorning(25 != 25)
         public string five()
         {
-            return "";
+            return "Good day!";
         }
 
         //TODO: 6. Use a conditional statement to return "Correct!" if the input is more than 7
         // or "Wrong!" if not
         public string six(int num)
         {
-            throw new NotImplementedException();
+            if (num > 7) {
+                return "Correct!";
+            }
+            else {
+                return "Wrong!";
+            }
         }
 
         //TODO: 7. Use a conditional statement to return "Correct!" if the input is false
         // or "Wrong!" if not
         public string seven(bool boolean)
         {
-            throw new NotImplementedException();
+            if (!boolean) {
+                return "Correct!";
+            }
+            else
+            {
+                return "Wrong!";
+            }
         }
 
         //TODO: 8. Use a conditional statement to return "Correct!" if numOne is more than or equal to numTwo
         // or "Wrong!" if not
         public string eight(int numOne, int numTwo)
         {
-            throw new NotImplementedException();
+            if (numOne >= numTwo) {
+                return "Correct!";
+            }
+            else
+            {
+                return "Wrong!";
+            }
         }
 
         //TODO: 9. Use a conditional statement to return true if the array provided is not empty
         // or false if it is empty
         public bool nine(int[] nums)
         {
-            throw new NotImplementedException();
+            if (nums.Length != 0 ) {
+                return true;
+            }
+            else
+            {
+                return false;
+            }
         }
 
         //TODO: 10. Use a conditional statement to return true if the provided string contains the word
@@ -110,8 +133,15 @@ public bool nine(int[] nums)
         // https://www.w3schools.com/java/java_ref_string.asp
         public bool ten(string sentence)
         {
-            throw new NotImplementedException();
+            if (sentence.Contains("milk")) {
+                return true;
+            }
+            else
+            {
+                return false;
+            }
         }
+        
 
         //TODO: 11. Use conditional statements to return the number 3 if the provided string contains
         // the word milk. Return the number 6 if the provided string contains the word coffee.
@@ -119,14 +149,29 @@ public bool ten(string sentence)
         // Otherwise, return the number 0.
         public int eleven(string sentence)
         {
-            throw new NotImplementedException();
+            int value = 0;
+            if (sentence.Contains("milk"))
+            {
+                value += 3;
+            }
+            if (sentence.Contains("coffee"))
+            {
+                value += 6;
+            }
+            return value;
         }
 
         //TODO: 12. Use conditional statements to return true if num is more than or equal to lower and is
         // less than or equal to upper, otherwise return false.
         public bool twelve(int num, int lower, int upper)
         {
-            throw new NotImplementedException();
+            if (num >= lower && num <= upper) {
+                return true;
+            }
+            else
+            {
+                return false;
+            }
         }
 
         /*
@@ -141,7 +186,30 @@ public bool twelve(int num, int lower, int upper)
          */
         public string thirteen(int age)
         {
-            throw new NotImplementedException();
+            if (age == 0)
+            {
+                return "Baby";
+            }
+            else if (age > 0 && age <= 4)
+            {
+                return "Toddler";
+            }
+            else if (age > 4 && age <= 12)
+            {
+                return "Child";
+            }
+            else if (age > 12 && age <= 19)
+            {
+                return "Teenager";
+            }
+            else if (age > 19)
+            {
+                return "Adult";
+            }
+            else
+            {
+                return "";
+            }
         }
     }
 }