Dear Farrah,

 Please consult

https://sites.math.rutgers.edu/~zeilberg/Hist21/q2S.pdf

for the full solutions.

You got 9 points (out of 10). # 3 was wrong. #4 was right, but you should have explained. This time I did not take any points off, but in the test I will.

 Best wishes,

   Dr. Z.