(a) Write a well-commented MATLAB function program mysolvecheck with input a number n that makes a random n x n matrix A and a random vector b, solves the linear system Ax = b, calculates the scalar residual r = || Ax b||, and outputs that number as r. (b) Write a well-commented MATLAB script program that calls mysolvecheck 10 times each for n = 5, 10, 20, 40, 80, and 160, then records and averages the results and makes a log-log plot of the average r vs. n. Once your program is running correctly, increase the maximum n (by factors of 2) until the program stops running within 5 minutes