diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 00000000..09799671
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,10 @@
+language: csharp
+solution: TravisCI.sln
+branches:
+  only:
+  - master
+install:
+  - nuget restore TravisCI.sln
+script:
+  - msbuild /p:Configuration=Release TravisCI.sln
+  - mono ./packages/NUnit.ConsoleRunner.*/tools/nunit3-console.exe ./Tests/bin/Release/Tests.dll
diff --git a/Console/Program.cs b/Console/Program.cs
index b3fcdf6a..f0c618ae 100644
--- a/Console/Program.cs
+++ b/Console/Program.cs
@@ -84,7 +84,7 @@ public static double Divide(string x, string y)
         // Implement this method following a similar pattern as above
         public static double Power(string x, string y)
         {
-            throw new NotImplementedException();
+            return Math.Pow(double.Parse(x), double.Parse(y));
         }
     }
 
diff --git a/Tests/UnitTests.cs b/Tests/UnitTests.cs
index 84cde036..90ca6e7a 100644
--- a/Tests/UnitTests.cs
+++ b/Tests/UnitTests.cs
@@ -31,5 +31,101 @@ public void Add_Null()
         }
 
         // Implement 3 tests per operation, following a similar pattern as above
+        [Test]
+        public void Subtract_ValidRisal()
+        {
+            Assert.AreEqual(-1, Program.Subtract("1", "2"));
+            Assert.AreEqual(1, Program.Subtract("3", "2"));
+            Assert.AreEqual(0, Program.Subtract("7", "7"));
+        }
+
+        [Test]
+        public void Subtract_InvalidRisal()
+        {
+            Assert.Throws<FormatException>(() => Program.Subtract("1", "a"));
+            Assert.Throws<FormatException>(() => Program.Subtract("a", "1"));
+            Assert.Throws<FormatException>(() => Program.Subtract("a", "a"));
+        }
+
+        [Test]
+        public void Subtract_NullRisal()
+        {
+            Assert.Throws<ArgumentNullException>(() => Program.Subtract("1", null));
+            Assert.Throws<ArgumentNullException>(() => Program.Subtract(null, "1"));
+            Assert.Throws<ArgumentNullException>(() => Program.Subtract(null, null));
+        }
+
+        [Test]
+        public void Multiply_ValidRisal()
+        {
+            Assert.AreEqual(2, Program.Multiply("1", "2"));
+            Assert.AreEqual(6, Program.Multiply("3", "2"));
+            Assert.AreEqual(35, Program.Multiply("5", "7"));
+        }
+
+        [Test]
+        public void Multiply_InvalidRisal()
+        {
+            Assert.Throws<FormatException>(() => Program.Multiply("1", "a"));
+            Assert.Throws<FormatException>(() => Program.Multiply("a", "1"));
+            Assert.Throws<FormatException>(() => Program.Multiply("a", "a"));
+        }
+
+        [Test]
+        public void Multiply_NullRisal()
+        {
+            Assert.Throws<ArgumentNullException>(() => Program.Multiply("1", null));
+            Assert.Throws<ArgumentNullException>(() => Program.Multiply(null, "1"));
+            Assert.Throws<ArgumentNullException>(() => Program.Multiply(null, null));
+        }
+
+        [Test]
+        public void Divide_ValidRisal()
+        {
+            Assert.AreEqual(1, Program.Divide("2", "2"));
+            Assert.AreEqual(1.5, Program.Divide("3", "2"));
+            Assert.AreEqual(5, Program.Divide("15", "3"));
+        }
+
+        [Test]
+        public void Divide_InvalidRisal()
+        {
+            Assert.Throws<FormatException>(() => Program.Divide("1", "a"));
+            Assert.Throws<FormatException>(() => Program.Divide("a", "1"));
+            Assert.Throws<FormatException>(() => Program.Divide("a", "a"));
+        }
+
+        [Test]
+        public void Divide_NullRisal()
+        {
+            Assert.Throws<ArgumentNullException>(() => Program.Divide("1", null));
+            Assert.Throws<ArgumentNullException>(() => Program.Divide(null, "1"));
+            Assert.Throws<ArgumentNullException>(() => Program.Divide(null, null));
+        }
+
+        [Test]
+        public void Power_ValidRisal()
+        {
+            Assert.AreEqual(1, Program.Power("1", "2"));
+            Assert.AreEqual(9, Program.Power("3", "2"));
+            Assert.AreEqual(1, Program.Power("5", "0"));
+        }
+
+        [Test]
+        public void Power_InvalidRisal()
+        {
+            Assert.Throws<FormatException>(() => Program.Power("1", "a"));
+            Assert.Throws<FormatException>(() => Program.Power("a", "1"));
+            Assert.Throws<FormatException>(() => Program.Power("a", "a"));
+        }
+
+        [Test]
+        public void Power_NullRisal()
+        {
+            Assert.Throws<ArgumentNullException>(() => Program.Power("1", null));
+            Assert.Throws<ArgumentNullException>(() => Program.Power(null, "1"));
+            Assert.Throws<ArgumentNullException>(() => Program.Power(null, null));
+        }
     }
 }
+