I wish to answer for 3 and 4,

4 is depend on 3.

please put more explanation,

The answer that I got from this site give this error when I tried to execute the code.

(main.cpp:5:20: fatal error: circle.h: No such file or directory #include "circle.h")

3. A point in the x-y plane is represented by its x-coordinate and y-coordinate. Design a class, pointType, that can store and process a point in the x-y plane. You should then perform operations on the point, such as showing the point, setting the coordinates of the point, printing the coordinates of the point, returning the x-coordinate, and returning the y-coordinate. Also, write a test program to test the various operations on the point.

4. Every circle has a center and a radius. Given the radius, we can determine the circles area and circumference. Given the center, we can determine its position in the x-y plane. The center of a circle is a point in the x-y plane. Design a class, circleType, that can store the radius and center of the circle. Because the center is a point in the x-y plane and you designed the class to capture the properties of a point in Programming Exercise 3, you must derive the class circleType from the class pointType. You should be able to perform the usual operations on a circle, such as setting the radius, printing the radius, calculating and printing the area and circumference, and carrying out the usual operations on the center.