If sam drops a 40 kg mass from a height of 20 meters on earth how much was the potential energy of the mass before he dropped it

Question

a-800 j
b-784 n-m
c-800 n-m
d-7840 j
e- 200 j

Answer 1

PE is measured in J or N-m

PE = mgh

Answer 2

so would the answer be B