HW help please...

would youpleae help me in this problemin my homework...
the question is as follows..

an early atmospheric engine has a sinle horizontal cylinder with a 3.2ft bore, a 9.0ft stroke, and no clearance volume. After a charge of gunpowder is set off in the open cylinder, the conditions in the cylinder are ambient pressure and a temperature of 540 degrees F. the piston is now locked in position and the cylinder is closed. After cooling to ambient temperature, the piston is unlocked and allowed to move. the power stroke is at constant temperature and lasts until pressure equilibrium is obtained. Assume te gas in the cylinder is air, and the piston motion is frictionless..
ambient conditions are 70 degrees F and 14.7 psia
calculate:
a- possible lifting force at start of power stroke
b- length of effective power stroke.
c- cylinder volume at end of power stroke..

please help me..
it is a bit higher than my level but i do want to learn aoutit..

i hope i could help u..

but am not so sure..

i think u should try using the ideal gas equations

PV = nRT

so (P1V1)/(n1T1) = (P2V2)/(n2T2)

i hope this helps..
i know its not the answer u want but it is a way to begin..