10 moles of an ideal gas, initially at a temperature of 200 K, are compressed in a thermally insulated closed piston-cylinder device in a mechanically reversible isothermal process. The volume of the gas is equal to 160000 cm3 in the initial state ane equal to 40000 cm3 in the final state. Find the:
a- pressure in the initial state;
b- temperature in the final state;
c- pressure in the final state;
d- mechanical work of this process;