In this lab you are to write a program that calculates a student's final grade and outputs the final letter grade to the console using functions. two tests scores and one homework score will be supplied by the user. to calculate the final score assume that the tests are each worth 40% and the homework is worth 20% of the total score. you should implement and use the following two functions: 1) calcfinalscore: this function is a value-returning function whose purpose is to compute the final score for a student. it takes three parameters: test1, test2, and hw (all doubles), and returns the final score as a double. 2) printfinalscore: this function is a non value-returning function that outputs a student's final score and letter grade to the console. it takes the parameter finalscore (a double). the breakdown of letter grades is as follows: 90 or above is an a, 80 to 90 is a b, 70 to 80 is a c, 60 to 70 is a d, and less than 60 is a big fat f.