Three moles of an ideal gas (with temperature-independent Cp = (7/2)R, Cv = (5/2)R) is contained in a horizontal piston/cylinder arrangement. The piston has an area of 0.1m^2 and mass of 500 g. The initial pressure in the piston is 101 kPa. Determine the heat that must be extracted to cool the gas from 375 C to 275 C at a.) constant pressure; b.) constant volume.