Question 3 Consider the following functions: void doit (int &a, ntb) a-a + 5; void doIt2 (int a, int& b) a 5 b+5 void doIt3 (int & a, int& b) a- a+ 5 Fix any errors in the above functions and write a main program that prompts the user for two integer numbers (numl and num2). Then, the main program calls the functions dolt, dolt2, and dolt3 with num1 and num2 as parameters. The main program will print the content of numl and num2 to the screen after each function is called. Add an addendum to the test plan to explain for each function the difference between a and b