Programming Basi Complete the following steps: 1. Write a C++ statement that includes the header file iostream 2. Write a C++ statement that allows you to use cin cout , and endl without the prefix std: 3. Write C++ statement(s) that declare the following variables: num1 , nu 2 nun3, and average of type int 4. Write C++ statements that store 125 into num1, 28 into num2, and -25 into nun3 5. Write a C++ statement that stores the average of numi , nun2 and nun3 into average 6. Write C++ statement(s) that output the values of nuni , num2 , nun3 and average 7. Click the Run button to compile and run your project