3. On the General server, use vi/vim to create a file called circle.c and enter the following C code: #include int main() { } float radius, area; printf("Enter the radius: "); scanf("%f", &radius); area = 3.1416 * radius * radius; printf("Area = %f ", area); Write a macro for the value 3.1416 and another macro to calculate the area of a circle given the radius as a parameter. Copy and paste your code into your submission. Compile the program with the following: gcc -save-temps circle.c Use the more command to view the file called a-circle.i and go the bottom to see what the preprocessor has done to the code. Copy and paste the code from the end of that file (the last 10 or so lines) into your submission. 15 pts.