An ideal gas expands isentropically through a converging nozzle from a large tank at 120 lbf/in.2, 6008R, and discharges into a region at 60 lbf/in.2 Determine the mass flow rate, in lb/s, for an exit flow area of 1 in.2, if the gas is
(a) air, with k 5 1.4.
(b) carbon dioxide, with k 5 1.26.
(c) argon, with k 5 1.667.