Improved the codes in Class Car,

src/main/java/org/model/Car.java

@@ -32,13 +32,12 @@ public abstract class Car extends Vehicle implements Serviceable {
         System.out.println(getMileage());
         System.out.println(seats);
     }
-    
+
 
     //Implements:
     public boolean needsService(Vehicle v) {
-        double mileage = getMileage();
-        if (mileage > 10000) {return true;}
-        else {return false;}
+        double mileage = v.getMileage();
+        return (mileage > 10000);
     }
 
     public void performService() {