Dear Nina,

 Please consult

https://sites.math.rutgers.edu/~zeilberg/Hist21/mt1S.pdf

for the full solutions.

You got  91 points (out of 120).

Here is what you got wrong:

#3: -7 points (started correctly, but the end result is nonsense(

#7: -2 points (EF is a sum of DISTINCT reciprocals)

#8: -10 points (see answer key)

#12: -10 points (see answer key)







 Best wishes,

   Dr. Z.