a vertical cylinder closed at bottom end contains $24$ cubic centimeter of air at $323$ k$.$it has a frictionless cylinder operating from the top end with a fixed mass of $30$ kg$.$ the cross$-$sectional area of the piston is $150$ square cm$.$The outside is atMospheric condition with a pressure of $1$ bar $.$ DETermine the gas pressure and mass. given specific heat capacities at constant pressure and volume of $1005$ J$/$kgK and $718$ J$/$kg k respectively.