Calculate the gravitational potential energy gained by the mass g=9.8N. if a crane lifts a 75 kg mass a height of 8m

Plss anybody know how to do this? ? i need the answers from a through d

If 2 moles of co_2 at 2l and 500k are expanded reversibly to 20l, more work can be obtained from an adiabatic process than from an isothermal process. is the above statement true or false?

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2