5.73 A compressor supplies gas to an 8 m tank. The inlet mass flow rate is given by m = 0.5Po/p (kg/s), where p is the density in the tank and po is the initial density. Find the time it would take to increase the density in the tank by a factor of 2 if the initial density is 1.8 kg/m^3. Assume the density is uniform throughout the tank.