SummaryIn this lab, you complete a partially written C++ program that includes a function named multiplyNumbers() that multiplies two int values to find their product. Three ints should be passed to the multiplyNumbers() function, the two numbers to be multiplied (num1 and num2) should be passed by value, and another int (product) to hold the product of the two numbers should be passed by reference, enabling the multiplyNumbers() function to change its value. The source code file provided for this lab includes the necessary variable declarations and input and output statements. Comments are included in the file to help you write the remainder of the program. Instructions:Open the source code file named MultiplyTwo. cpp using the code editor. Write the multiplyNumbers() function, the function declaration, and the function call as indicated by the comments. Execute the program by clicking "Run Code."Rewrite the multiplyNumbers() function to pass the two numbers (num1 and num2) by value and to pass product by address. Execute the program. It should generate the same output.// MultiplyTwo. cpp - This program calculates the product of two numbers.// It demonstrates pass by reference and then pass by address.// Input: None// Output: The product of two numbers#include using namespace std;// Write function declaration hereint main(){int num1 = 10;int num2 = 20;int product = 0;// Print value of product before function callcout << "Value of product is: " << product << endl;// Call multiplyNumbers using pass by reference for product// Print value of calculated productcout << num1 << " * " << num2 << " is " << product << endl;return 0;} // End of main function// Write multiplyNumbers function here; use pass by reference for result of multiplication. Then use pass by address.