Which of the following is a unique feature of the Earth's environment that aerospace engineers needed to imitate on a spacecraft in order to make manned spaceflight possible?

A. The Earth has a strong magnetic field.
B. The Earth has an atmosphere rich in carbon dioxide and hydrogen.
C. The Earth has a strong gravitational field.
D. The Earth has an atmosphere rich in nitrogen and oxygen.

The average atmospheric pressure on earth is approximated as a function of altitude by the relation patm = 101.325 (1 − 0.02256z)5.256, where patm is the atmospheric pressure in kpa, and z is the altitude in km with z = 0 at sea level. determine the approximate atmospheric pressures at atlanta (z = 306 m), denver (z = 1610 m), mexico city (z = 2309 m), and the top of mount everest (z = 8848 m).