2 thermo problems which I need answered in full

1. Air in a piston/cylinder expands reversibly and adiabatic.  The initial
temp is 507K and the pressure in 600Kpa.  The final pressure is 120Kpa.

Find
a) mass of the air in kg
b) final temp assuming constant specific heat.
c) find work

2. Heat Pump problem.  30,000 kj/h to maintain a
building at 20 degrees C
with outside temp of 0 degrees C.

Find
a) find min power to operate heat pump in KW
b) find maximum COP for heat pump
c) if actual COP is 0.5, what is required to run heat
pump?