For this assignment, you are to write a program that does the following: (C++) • read exam scores from a file name data.txt into an array, and • after reading all the scores, output the following to the monitor: the average score and the total number of scores. In addition, the program must use the following functions: //precondition: fileName is name of the file to open, inFile is the input file 2 of 2 //postcondition: inFile is opened. If inFile cannot be opened, a message is // written to cout and the program exits void openFile(string filename, ifstream& inFile); //precondition: a score array, size is a’s length //postcondition:avg contains score score average float calculateAverage(float a, int size) Remember to perform all required operations on the files, otherwise you receive a significant deduction. Failure to conform to the specification will result in significant deductions (up to 50 points). Finally, every function must be commented with preconditions and post conditions. Failure to include these things will result in a 20 point deduction. Each line of the data file will contain a score. You can assume that each non-empty line in the file contains a score and nothing else. You can assume that there will be no more than 25 scores in the file, but there may be any number from two to 25.