diff --git a/pom.xml b/pom.xml
index e7cb4f6b..3af9ec0b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -7,6 +7,32 @@
     <groupId>com.zipcodewilmington</groupId>
     <artifactId>scientific_calculator</artifactId>
     <version>1.0-SNAPSHOT</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>7</source>
+                    <target>7</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    <dependencies>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>RELEASE</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
 
 
 </project>
\ No newline at end of file
diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorOperator.java b/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorOperator.java
new file mode 100644
index 00000000..ebd33e0b
--- /dev/null
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorOperator.java
@@ -0,0 +1,54 @@
+package com.zipcodewilmington.scientificcalculator;
+
+//comments
+
+public class CalculatorOperator {
+
+    public static double addition (double a, double b) {
+        double addition = a + b;
+        return addition;
+    }
+
+    public static double subtraction
+            (double a, double b) {
+        double subtraction = a - b;
+        return subtraction;
+    }
+
+    public static double multiplication (double a, double b) {
+        double multiplication = a * b;
+        return multiplication;
+    }
+
+    public static double division (double a, double b) {
+        double division = a / b;
+        return division;
+    }
+
+    public static double square (double a) {
+        double square = Math.pow(a,2);
+        return square;
+    }
+
+    public static double squareRoot (double a) {
+        double squareRoot = Math.sqrt(a);
+        return squareRoot;
+    }
+
+    public static double exponents (double a, double b) {
+        double exponent = Math.pow(a,b);
+        return exponent;
+    }
+
+    public static double multiplicativeInverse (double a) {
+        double multiplicativeInverse = 1/a;
+        return multiplicativeInverse;
+    }
+
+    public static double additiveInverse (double a) {
+        double additiveInverse = a * -1;
+        return additiveInverse;
+    }
+
+}
+
diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java b/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
index 83f0e97f..282c1c9e 100644
--- a/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
@@ -1,5 +1,7 @@
 package com.zipcodewilmington.scientificcalculator;
 
+// comments
+
 import java.util.Scanner;
 
 /**
@@ -23,10 +25,16 @@ public static String getStringInput(String prompt) {
     }
 
     public static Integer getIntegerInput(String prompt) {
-        return null;
+        Scanner scanner = new Scanner(System.in);
+        println(prompt);
+        int userInput = scanner.nextInt();
+        return userInput;
     }
 
     public static Double getDoubleInput(String prompt) {
-        return null;
+        Scanner scanner = new Scanner(System.in);
+        println(prompt);
+        double userInput = scanner.nextDouble();
+        return userInput;
     }
 }
diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java b/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
index 5f421325..c3770264 100644
--- a/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
@@ -1,5 +1,7 @@
 package com.zipcodewilmington.scientificcalculator;
 
+// comments
+
 /**
  * Created by leon on 2/9/18.
  */
@@ -7,11 +9,30 @@ public class MainApplication {
     public static void main(String[] args) {
         Console.println("Welcome to my calculator!");
         String s = Console.getStringInput("Enter a string");
-        Integer i = Console.getIntegerInput("Enter an integer");
+        Double i = Console.getDoubleInput("Enter a double");
         Double d = Console.getDoubleInput("Enter a double.");
 
         Console.println("The user input %s as a string", s);
         Console.println("The user input %s as a integer", i);
         Console.println("The user input %s as a d", d);
     }
-}
+
+    public static double calculator (String s, double i, double d) {
+        double result = 0;
+            switch (s) {
+                case "+":
+                    result = CalculatorOperator.addition(i, d);
+                    break;
+                case "-":
+                    result = CalculatorOperator.subtraction(i, d);
+                    break;
+                case "*":
+                    result = CalculatorOperator.multiplication(i, d);
+                    break;
+                case "/":
+                    result = CalculatorOperator.division(i,d);
+                    break;
+            }
+            return result;
+        }
+    }
diff --git a/src/test/java/com/zipcodewilmington/scientific_calculator/TestMainApplication.java b/src/test/java/com/zipcodewilmington/scientific_calculator/TestMainApplication.java
index 94e8d987..c53f6a41 100644
--- a/src/test/java/com/zipcodewilmington/scientific_calculator/TestMainApplication.java
+++ b/src/test/java/com/zipcodewilmington/scientific_calculator/TestMainApplication.java
@@ -1,7 +1,67 @@
 package com.zipcodewilmington.scientific_calculator;
 
+import com.zipcodewilmington.scientificcalculator.CalculatorOperator;
+import com.zipcodewilmington.scientificcalculator.MainApplication;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+
 /**
  * Created by leon on 2/9/18.
  */
 public class TestMainApplication {
+    @Test
+    public void addition() {
+        Assertions.assertEquals(6 , CalculatorOperator.addition(3, 3));
+    }
+
+    @Test
+    public void subtraction() {
+        Assertions.assertEquals(-1 , CalculatorOperator.subtraction(3, 4));
+    }
+
+    @Test
+    public void multiplication() {
+        Assertions.assertEquals(17 , CalculatorOperator.multiplication(17, 1));
+    }
+
+    @Test
+    public void division() {
+        Assertions.assertEquals(1 , CalculatorOperator.division(22, 22));
+    }
+
+    @Test
+    public void squareTest() {
+        Assertions.assertEquals(9 , CalculatorOperator.square(3));
+    }
+
+    @Test
+    public void squareRootTest() {
+        Assertions.assertEquals(5 , CalculatorOperator.squareRoot(25));
+    }
+
+    @Test
+    public void exponentsTest() {
+        Assertions.assertEquals(4 , CalculatorOperator.exponents(2,2));
+    }
+
+    @Test
+    public void multiplicativeInverseTest() {
+        Assertions.assertEquals(1 , CalculatorOperator.multiplicativeInverse(1));
+    }
+
+    @Test
+    public void additiveInverseTest() {
+        Assertions.assertEquals(4 , CalculatorOperator.additiveInverse(-4));
+    }
+
+    @Test
+    public void calculatorTest() {
+        Assertions.assertEquals(5.2 , MainApplication.calculator("+", 2.2, 3.0));
+        Assertions.assertEquals(-1 , MainApplication.calculator("-", 2.0, 3.0));
+        Assertions.assertEquals(6 , MainApplication.calculator("*", 2.0, 3.0));
+        Assertions.assertEquals(4 , MainApplication.calculator("/", 12, 3));
+    }
+
+
 }