Answer:
Step-by-step explanation:
Remark
You could do this by converting the distance but the much more common way is to use kg and m.
Formula
PE = m * g * h
Givens
m = 40000 grams
m = 40000 grams * 1kg/1000 grams = 40 kg
g = 9.81
h = 35 m
Solution
PE = 40 * 9.81 * 35
PE = 13734 Joules