At the inlet to the combustor of a supersonic combustion ramjet (SCRAMjet), the flow Mach number is supersonic. For a fuel-air ratio (by mass) of 0.03 and a combustor exit temperature of \(4800^{\circ} \mathrm{R}\), calculate the inlet Mach number above which the flow will be unchoked. Assume one-dimensional frictionless flow with \(\gamma=1.4\), with the heat release per slug of fuel equal to \(4.5 \times 10^{8} \mathrm{ft} \cdot \mathrm{lb}\).