Write a main function and the following functions to compute

Write a MAIN function and the following funcations to compute the stress and strain in a steel rod of diameter D (inches) and length L (inches) subject to the compress loads P of 10,000 to 1,000,000 pounds in increments of 100,000 pounds. The modulus of elasticity E for steel is 30 x 10 to the 6th power.