INHERITANCE AND POLYMORPHISM - Java Programming: From Problem Analysis to Program Design - page 716

Further suppose that the class GradStudent has the following method:
public void printGrades(String status)
How many printGrade methods will the class GradStudent have and
what are their headings?

Suppose that you have the following class:
public class classA
{

16.

private int x; //Line 1

protected void setX( int a) //Line 2

{ //Line 3

x = a; //Line 4

}

}

What is wrong with the following code?
public class Exercise16 //Line 5

{

public static void main(String[] args) //Line 6
{

classA aObject; //Line 7

aObject.setX(4); //Line 8

}

}

Suppose that you have the following class definitions:
public class One
{

17.

private int x;
private int y;

public void print()
{

System.out.println(x + " " + y);
protected void setData( int u, int v)
{

x = u;
y = v;

}

}
Consider the following class definitions:
public class Two extends One
{

private int z;