To answer the question above, we will have to use some calculus approach to this problem.
volume of sphere = (4/3)(pi)(radius^3) = (4/3)(pi)(9^3) = 972pi
mass = (density)(volume) = (972pi)(1,000) = 972,000pi
force = (mass)(acceleration or gravity here) = (972,000pi)(9.8) = 9,525,600pi
work = (force)(distance) = (9,525,600pi)(4.5) = 42,865,200pi J
I hope my answer helped you with your problem
