A 5 cm diameter piston-cylinder device contains 0.04 kg of an ideal gas at equilibrium at 100 kPa, 300 K occupying a volume of 0.5 m3. Determine (a) the gas density (ρ), and (b) the specific volume (v). (c) A weight is now hung from the piston (see figure) so that the piston moves down to a new equilibrium position. Assuming the piston to be weightless, determine the mass of the hanging weight necessary to reduce the gas pressure to 50 kPa. (Data supplied: g = 9.81 m/s2; Outside pressure: 100 kPa).