JAVA Interfaces and Abstract Classes Given the following piece of code:public class School{ public abstract double numberOfStudent();}which of the following statements is true? The keywords public and abstract cannot be used together. Class School must be defined abstract. The method numberOfStudent() in class School must have a body. You must add a return statement in method numberOfStudent(). The keywords public and abstract cannot be used together. Class School must be defined abstract. The method numberOfStudent() in class School must have a body. You must add a return statement in method numberOfStudent(). ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following class definitions defines a legal abstract class? abstract class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } class A { abstract void unfinished(); } class A { abstract void unfinished() { } } abstract class A { abstract void unfinished(); } public class abstract A { abstract void unfinished(); } class A { abstract void unfinished(); } class A { abstract void unfinished() { } } ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following declares an abstract method in an abstract Java class? public abstract void method() {} public abstract void method(); public abstract method(); public void abstract Method(); public void method() {} public abstract void method() {} public abstract void method(); public abstract method(); public void abstract Method(); public void method() {} ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Which of the following statements regarding abstract classes are true? All of these An abstract class can be extended. An abstract class can be used as a data type. A subclass of a non-abstract superclass can be abstract. A subclass can override a concrete method in a superclass to declare it abstract. All of these An abstract class can be extended. An abstract class can be used as a data type. A subclass of a non-abstract superclass can be abstract. A subclass can override a concrete method in a superclass to declare it abstract. ANSWER DOWNLOAD EXAMIANS APP
JAVA Interfaces and Abstract Classes Suppose A is an abstract class, B is a concrete subclass of A, and both A and B have a default constructor. Which of the following is correct?1. A a = new A();2. A a = new B();3. B b = new A();4. B b = new B(); 2 and 3 2 and 4 1 and 3 3 and 4 1 and 2 2 and 3 2 and 4 1 and 3 3 and 4 1 and 2 ANSWER DOWNLOAD EXAMIANS APP