You are required to write a C program on Unix/Linux in which the parent process creates three child processes, lets them run concurrently, and waits for them to return and prints their exit status. The three child processes are assigned different tasks.

Child one is to calculate and display the average mark of a class of twenty students for a unit. Child one is required to get the marks from the standard input (i.e. the keyboard). Child two is to load a program called wc (word count) to count file1.

Child two is required to get file1 by the command line argument. Child three is to modify file2 by first inserting this is the updated version. at the beginning of this file and then replacing all the occurrences of the word run by execute and examine by study. You are required to write your OWN program for the file update.

Child three is required to get file2 by the command line argument.