Mach I (the Speed of Sound) is approximately 1,236 km/h (738 mp/h).
This is dependent on the air pressure. At sea level, the speed of sound is about 760 mph; at high altitude it reduces closer to 600 mph.
1335 kmph
3675 KPH
1790
500 mph = 804.7 kph
fast.
600 kph = 372.8 mph
Faster than 58 kph.
175*1.6=280 kph
211 mph = 339.57 kph
98 kph = 60.9 mph
40,000 kph = 24,854.85 mph
Mach 0.8-1.0