<prompt> Kuandika C kazi kwa ajili ya mahesabu ya eneo la karibu ya mduara.  <response>: Here is a C function that can be used to calculate the approximate area of a circle:cincludeincludeusing namespace std;double circleAreadouble radius const double PI 3.14159265; return powradius,2PI;int main double r 5.0; cout The area of a circle with radius r circleArear endl; return 0;This function takes in the radius of the circle, radius, as a parameter. The value of PI is defined as a constant, since it is a fixed value. The function returns the calculated area of the circle using the formula area PI radius radius. In the main function, we test the circleArea function with a radius of 5.0, and it returns the approximate area of the circle. 