How to determine shape from std deviation and mean

Solve the problem. a student earned grades of c, a, b, and a in four different courses. those courses had these corresponding numbers of credit hours: 4, 5, 1, and 5. the grading system assigns quality points to letter grades as follows: a = 4, b = 3, c = 2, d = 1, and f = 0. compute the grade point average (gpa) and round the result to two decimal places. 3.40 3.50 8.75 2.18

Given the graphed function below which of the following orders pairs are found on the inverse function

If t17 = 3 (t5) in an arithmetic progression, find t1 in terms of d.