一些简单的C++程序题

The part is just about the basic part of C++ programming, and no Class or subsequent knowledge is involved.

Question :

1. Write a program that displays the area and perimeter of a circle that has a radius of 5.5 using the following from.

Perimeter=2*radius*π.

Area=radius*radius*π.

The answer of  question 1

2.Write a program that displays the area and perimeter of a rectangle with of 4.5 and height of 7.9 using the following formula:                          

 Area=width*height 

The answer of  question 2

3.Enter the length,width,and height of a Cuboid,and output its volume.

The answer of  question 3