Everything is passing the tests

AliceAndBobEngine.java

@@ -10,26 +10,38 @@ public class AliceAndBobEngine {
      * @return `true` if `input` is "Alice"
      */
     public Boolean isAlice(String input) {
-        return null;
+        if (input == "Alice") {
+            return true;  
+    }   else {
+        return false;
     }
+}
 
     /**
      * return `true` if the input value is "Bob"
      * @param input - this value is variable: it has the potential to be many things
      * @return `true` if `input` is "Bob"
      */
     public Boolean isBob(String input) {
-        return null;
+        if (input == "Bob") {
+            return true;
+    }   else {
+        return false;
     }
+}
 
     /**
      * return `true` if the input value is "Alice" or "Bob"
      * @param input - this value is variable: it has the potential to be many things
      * @return `true` if `input` is "Alice" or "Bob"
      */
     public Boolean isAliceOrBob(String input) {
-        return null;
+        if (input == "Alice" || input == "Bob") {
+            return true;
+    }   else {
+        return false;
     }
+}
 
     /**
      * if the input value is "Alice" or "Bob", then
@@ -42,6 +54,10 @@ public Boolean isAliceOrBob(String input) {
      * @return respective String value
      */
     public String getGreeting(String input) {
-        return null;
+        if (input == "Alice" || input == "Bob") {
+            return "Hello, " + input + "!";
+        }   else {
+                return "Begone, " + input + "! You're a stranger!";
+        }
     }
 }

IsAliceOrBobTest.java

@@ -34,4 +34,8 @@ public void testIsAliceOrBobFalse() {
         }
     }
 
+
+
 }
+
+