Exercise1: Write a complete C++ program that gets three numbers (x,y and z ) from user and calculate the results of the given equations by using the following user defined functions. Function for a) double y( int x, int y ); Function for b ) double f( int x, int y, int z ); a) y= b) f= Exercise2: Write a complete C++ program that gets a number from user and checks if the number is odd number or even number by using the following user defined function. Then, if the number is even, then display a message as "The given number is even". Otherwise, display message as "The given number is odd". Function1: int isEven(int number); Exercise3: Write a complete C++ program that gets two numbers and an operand (+,,,/) from the user, calculate and display the results to the user by using the following user defined functions. (Hint: The Function 2 should be called inside of Function1). Function 1: void getNumber(); Function2: double calculate(int num1, int num2, char operand); Exercise4: Write a complete C++ program that gets quiz, midterm and final marks from the user. Then, calculate the average and display the result to user by using the following user defined functions. (Quiz: 20%, Midterm: 30%, Final: 50% ) Function1: double quizPercentage(int quiz); Function2: double midtermPercentage(int midterm); Function3: double finalPercentage(int final); Function4: void calcAverage(double quiz, double midterm, double final)