The safest value available. 0 if on the ground, the upper limit of survival in an aircraft, balloon etc...
Above 100,000 feet altitude (20 miles).
The higher the altitude the lower the temperature.
Altitude describes an object's position relative to sea level. An object in a position higher than sea level would have a positive altitude, sea level would have an altitude of zero, and any object below sea level would have a negative altitude.
Density Altitude is the altitude relative to the standard atmosphere conditions (ISA) at which the air density will be equal to the indicated at the place of observation.
The Challenger explosion occurred at an altitude of about 46,000 feet.
480 kts
30-35,000 feet
it is a deviation from the normal change of atmospheric properties with altitude
This depends on the region, altitude and month of the year.
In my opinion, 200 feet of altitude, either higher or lower, from the normal baseline altitude of the person, will have little to no affect on breathing or pulse.
high altitude chambers
The cruising altitude of a normal commercial jet airplane today is around 12,000 m (35,000 ft).
122 normal 120 high altitude
Yes
Grilling normal foods don't generally have any changes due to altitude. This is a problem more for people who are attempting to bake something that needs to rise.
Yes, on average, temperature decreases by 6.5°C per kilometer as altitude increases in the troposphere. This is known as the normal lapse rate. However, in some regions, temperature inversions can cause temperatures to increase with altitude.
A normal commercial jet can cruise at a speed of mach 0.85 or about 570 miles