19. What is the keyword we use to specify that some method is a "procedural" type method, has no reference to the object and when executed is name should be preceded by the name of the class rather than the name of the objects? (answer in 1 word, small letters) [/4) (1 Point) 20. Tick the correct statements about abstract methods and classes (1 Point) An abstract class cannot implement interfaces An abstract method must be overridden in a non-abstract subclass An abstract method is really just a method declaration An abstract class must contain an abstract method 21. Can a class in Java inherit directly from several classes at once? (1 Point) This is only possible in one particular case Yes, always No Yes, but only from abstract classes