For the answer to this question,
Thalia must consider the weight of the object and the mass of the sculpture. Weight and mass are different things. She should also consider the time on how long it will take to move it and where she'll move it.
I think it is the Milky Way.
Answer:
If efficiency is .22 then W = .22 * Q where Q is the heat input
Heat Input Q = 2510 / .22 = 11,400 J
Heat rejected = 11.400 - 2510 = 8900 J of heat wasted
Also, 8900 J / (4.19 J / cal) = 2120 cal