Question

Question 1 1 pts Which of the following is not a valid class name in Java? O MyClass MyClass1 My_Class MyClass# Question 2 1 pts Which of the following statements is False about instance variables and methods? Instance variables are usually defined with private access modifier. Instance variables are defined inside instance methods. Instance methods are invoked on an object of the class that contains the methods. A class can have more than one instance variables and methods.

Answer 1

Please find your answers below. Let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

Question 1:

Answer: MyClass#

Because special symbols except underscore (_) are not allowed in identifiers.

Question 2:

Answer: Instance variables are defined inside instance methods.

This is absolutely wrong since they are defined outside of all member functions.

Question 3:

Answer: Constructor can only be called using an object of that class.

This is wrong because constructors cannot be called using an object, it gets automatically invoked when an object is created

Question 4:

Answer: option d, public double FindSpeed(double d, double t){…}

This is wrong because constructor cannot have return types and neither do they return values.

Question 5:

Answer: The most possible answer is option a, which is below

Name: Mary Tweed        Age:10

Name: Steve Smith          Age:12

But there is also a problem, inside the method displayStudentDetails(), after “Name:”, there is no space at all. So the actual output should be like below.

Name:Mary Tweed         Age:10

Name:Steve Smith           Age:12

If this is deliberate, then the right option is “None of the above”

Question 6:

Answer: java.scanner

This is not a built in package. If you are thinking about Scanner class, it is located inside java.util package.

Question 7:

Answer: default

Question 8:

Answer: There are two answers for this. If you are calling this method from Rectangle class, both

double area = findArea(10.5, 5.5) ;

and

double area = Rectangle.findArea(10.5, 5.5);

are valid method calls. If you are calling from outside the Rectangle class, then only

double area = Rectangle.findArea(10.5, 5.5);

is valid.

Question 9:

Answer: An object can have at most one object reference pointing to it.

This is wrong, an object can have any number of object references.