A/An) ____________ is a contract in the form of a collection of method and property declarations. When a class implements (a/an) ____________, it promises to implement all of the methods and property getters and setters declared in that ____________. Select the best word to complete this sentence.

A/An can access all variables and methods of class.(a) datatype(c) fields(b) constructor(d) object

Given these class definitions, which of the following must occur within class S?public abstract class R{ private int a; protected double c; public abstract void doThis();}public class S extends R{}a.The doThis() method must be definedb.An accessor method must be created for instance variable ac.An accessor method must be created for instance variable c

In Java programming, the keyword used to implement an interface in a class is:Question 4Answera.usesb.extendsc.requiresd.implements

What is the purpose of the "implements" keyword in Java?Question 6Answera.It is used to create an instance of a class.b.It is used to mark a class as abstract.c.It is used to indicate that a class is a subclass.d.It is used to indicate that a class implements an interface.

a.It is used to call a constructor of the superclass. b.It can be used to call a static method in the superclass.c.It must always be the first line of code in a constructor. d.It can only be used in a subclass.