#include using namespace std; // area calculation program that employs functions // Albert Levi 17 July, 2002 void calculate_area(float radius) { float area; area = 3.14 * radius * radius; cout << "The area of a circle with radius " << radius << " is " << area << endl; } int main() { float a; cout << "Please enter the radius of the circle: "; cin >> a; calculate_area(a); calculate_area(2.5); calculate_area(a / 2); return 0; }