The owner of Harry’s Car Sales pays each salesperson a commission based on his or her quarterly sales. The sales ranges and corresponding commission rates are shown in Figure 6-43. The program should display an error message if the sales amount is less than 0.
Quarterly sales ($)                 Commission
0–20,000 ...............................    multiply the sales by 5%
20,001–50,000 .....................    multiply the sales over 20,000 by 7% and then
                                                    add 1,000 to the result
50,001 or more .....................    multiply the sales over 50,000 by 10% and then
                                                    add 3,100 to the result
Figure 6-43

a. Create an IPO chart for the problem, and then desk-check the algorithm seven times, using sales of 20000, 20001, 30000, 50000, 50001, 75000, and –3.

b. List the input, processing, and output items, as well as the algorithm, in a chart similar to the one shown earlier in Figure 6-27. Then code the algorithm into a program.

c. Desk-check the program using the same data used to desk-check the algorithm.

d. If necessary, create a new project named Introductory14 Project, and save it in the Cpp8\Chap06 folder. Enter your C++ instructions into a source file named Introductory14.cpp. Also enter appropriate comments and any additional instructions required by the compiler. Display the commission in fixed-point notation with two decimal places.

e. Save and run the program. Test the program using the same data used to deskcheck the program.