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GPA Calculator ons In this assignment you will be creating a GPA calculator. The computer should ask the user to enter a base grade, if it is +/, and the credits associated with 4 different classes. It should then compute your quarter GPA and display it. Sample interaction should look like the following: Enter letter(A,B.C,D,F) grade for course O: B Plus(+), Minus(-) or Straight(o):+ Credits: 4 Enter letter(AB.C,D,F) grade for course 1: A Plus(+), Minus(-) or Straight(x): Credits: 3 Enter letter(A,B.C,D,F) grade for course 2:B Plus(+), Minus(-) or Straight(x): x Credits: 3 Enter letter(A,B,C,D,F) grade for course 3: C Plus(+), Minus(-) or Straight(x):+ Credits: 2 GPA: 3.16666 It is best to build this in stages. The first stage should be to get the grade, plus/minus character, and credits from the user for a single course. Make sure you do this for a single course only at this stage. You will use a loop to do it for 4 courses later Once you have the two chars and one int from the user, you need to use the determine their number grade: Do this in 2 stages. First use the letter grade to determine the base number grade. A is 4, B is 3, C is 2, D is 1, and F is O. Do some printouts to test and make sure your code is working for this stage