1. Determine the Mach number of a car moving in standard air at a speed of
(a) 25 mph,
(b) 55 mph, and
(c) 100 mph.
2. The flow of an ideal gas may be considered incompressible if the Mach number is less than 0.3. Determine the velocity level in ft/s and in m/s for Ma = 0.3 in the following gases:
(a) standard air,
(b) hydrogen at 68 °F.