$6-8$E A steady$-$flow compressor is used to compress helium from $15$ psia and $70F$ at the inlet to $200$ psia and $600F$ at the outlet. The outlet area and velocity are $0\mathrm{.}01f{t}^2$ and $100f\frac{t}{s},$ respectively, and the inlet velocity is $50f\frac{t}{s}.$ Determine the mass flow rate and the inlet area. Answers: $0\mathrm{.}0704lb\frac{m}{s},0\mathrm{.}133f{t}^2$