Write a program that includes two functions. The first function should ask a salesperson for the dollar value of daily sales and then return this figure to the main program. The second function should calculate the salesperson's commission based on the following rates:

Sales..............................Commission

0-999.....................................3%

1,000-2,999..........................3.5%

3,000-up...............................4.5%

The dollar value of the calculated commission should be returned to the main program, which then displays it.