Modify the simulation program given in Computer Example 4.4 to allow the sampling frequency to be entered interactively. Examine the effect of using different sampling frequencies by executing the simulation with a range of sampling frequencies. Be sure that you start with a sampling frequency that is clearly too low and gradually increase the sampling frequency until you reach a sampling frequency that is clearly higher than is required for an accurate simulation result. Comment on the results. How do you know that the sampling frequency is sufficiently high?