Questions 18 - 20 pertain to the following class, Point:

public class Point { private double x; private double y; public Point() { this (0, 0); } public Point(double a, double b) { /* missing code */ } // ... other methods not shown } 

Which of the following correctly implements the equals method?

public boolean equals(Point p) { return (x == p.x && y == p.y ); } 

public void equals(Point p) { System.out.println(x == p.x && y == p.y); } 

public void equals(Point p) { return (x == p.x && y == p.y ); } 

public boolean equals(Point p) { return (x == Point.x && y == Point.y); } 

public boolean equals(Point p) { System.out.println(x == p.x && y == p.y); } 

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The default constructor sets x and y to (0, 0) by calling the second constructor. What could be used to replace /* missing code */ so that this works as intended?

a = 0; b = 0;

this (x, y);

this(0, 0);

x = a; y = b;

a = x; b = y;

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Which of the following correctly implements a mutator method for Point?

public double getX() { return x; } 

public void setCoordinates (double a, double b) { x = a; y = b; } 

None of the items listed.

public double getX() { return a; } 

public void setCoordinates (double a, double b) { Point p = new Point(a,b); }