Nitrogen at 60 psia and 300°F with a volume of 10 ft3 is allowed to expand in a polytropic process such that Pvn = C, where C is a constant. Determine the work done and the heat transfer during this process if the final volume is 50 ft3 and
a) n = 1.2,
b) n = 1.4,
c) n = 1.6.