(Computer-Assisted Instruction: Difficulty Levels) Exercises 5.35–5.37 developed a computer- assisted instruction program to help teach an elementary school student multiplication. Modify the program...

(Computer-Assisted Instruction: Difficulty Levels)

Exercises 5.35–5.37 developed a computer- assisted instruction program to help teach an elementary school student multiplication. Modify the program to allow the user to enter a difficulty level. At a difficulty level of 1, the program should use only single-digit numbers in the problems; at a difficulty level of 2, numbers as large as two digits, and so on.