Weight loss. If your cat is overweight, you will want to feed for 2 pounds less, or 40 fewer calories a day, and readjust every time your cat loses a pound, until you hit a healthy weight, and then maintain.  Differences in metabolism.
Since the speed of sound through the standard atmosphere is 761 mph (1,223 km/h) at sea level, Mach 2 then follows as 1,522 mph (2,447 km/h). If you were to ask how fast is Mach 2 at an altitude of 30,000 ft (9,150 m), we would use the same methodology to find out that it is only 1,356 mph (2,180 km/h) because the speed of sound generally decreases as altitude increases.
Best Answer: If you mean Mach 1, it is the speed of sound. The following values are all at sea level and 15 degrees C. Note the mach number is not a constant; it is temperature dependent. In miles per hour: 761 mph. In kilometers per hour: 1225 kph. In feet per second: 1116 ft/sec.