Develop a computer-assisted instruction program to teach an elementary-school student multiplication. This exercise suggests enhancements to that program. a) Modify the program to allow the user to...

Develop a computer-assisted instruction program to teach an elementary-school student multiplication. This exercise suggests enhancements to that program.

a)  Modify the program to allow the user to enter a grade-level capability. A grade level of 1 means to use only single-digit numbers in the problems, a grade level of 2 means to use numbers as large as two digits, and so on.

b)  Modify the program to allow the user to pick the type of arithmetic problems he or she wishes to study. An option of 1 means addition problems only, 2 means subtraction problems only, 3 means multiplication problems only, 4 means division problems only and 5 means to intermix randomly problems of all these types.