Hi, in problem #39, my calculations resulted in the n^2 + 1 in the numerator and the n^2 - 1 in the denominator compared to your answer of A.  Do you have work to share on this problem.  Thank you.  (AP Physics C:  Mechanics, Dynamics in 2 - Multiple Choice Practice Problems and #39 starts with "A small block is given a short push from the bottom....")

Maura, I'm emailing you the solution. I get n^2-1 in the numerator. Please let me know what you think.  John