Please help me
What is the ratio between the acceleration due to gravity of two hypothetical planets X and Y, if the mass of the

planet X is three times greater than the mass of the planet Y, and the radius of the planet X is twice greater of

the radius of the planet Y.

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.