1. Write a program that computes all twin primes between two values entered by the user. Twin primes are numbers that differ by two and are both primes, such as 1019 and 1021. 2. Write a function with...

1. Write a program that computes all twin primes between two values entered by the user. Twin primes are numbers that differ by two and are both primes, such as 1019 and 1021.

2. Write a function with prototype int NumDigits(num) that determines the number of digits in its parameter. Use the ideas of the previous exercise, but be sure that the function works for all integer values (including zero, which has one digit, and negative numbers—don’t forget about the function fabs).