Air flows in a duct, and a valve is quickly closed. A normal shock is observed to propagate back through the duct at a speed of \(1010 \mathrm{ft} / \mathrm{sec}\). The gas that has been brought to rest has a temperature and pressure of \(600^{\circ} \mathrm{R}\) and \(30 \mathrm{psia}\), respectively. What were the original temperature, pressure, and velocity of the air flow before the valve was closed?