Sample Input/output: (The average is supposed to be actually 74.33, so why did we get 742 How to fix it to get an accurate average resulta) 81 Enter three grades: 69 7 3 The grades that you entered are: Test3: 81 Test2: 73 Testi: 69 The sum of the grades is: 223 The average grade is: 74 Homework #2: Redo the above Exercise 2 to read the test info (a) from a file "test.txt". Then output the results (b) to a file "grade.txt