l_correct.java

public interface Car {
  public void startEngine();
}

public Ferrari implements Car {
  ...
  @Override
  public double startEngine() {
         //logic ...
  }
}

public Tesla implements Car{
  ...
  @Override
  public double startEngine() {
         if (!IsCharged)
            TurnOnCar();
       //logic ...
  }
}

public void letStartEngine(Car car) {
   car.startEngine();
}