Final answer:
Quito, Ecuador has an average altitude of 2,850 meters or 9,200 feet, making it the second-highest capital city in the world and is considered to be significantly above sea level (option A). The altitude of Quito is associated with an environmental consideration where air density decreases as altitude increases.
Step-by-step explanation:
The altitude of Quito, Ecuador, is frequently mentioned when discussing the city because it is notably high. At an average altitude of 2,850 meters, Quito is significantly above sea level. This places Quito as the second-highest capital city in the world, after La Paz in Bolivia, which has even higher elevations.
The altitude has implications on various environmental factors such as air density. According to Figure A4, which illustrates the Altitude-Air Density Relationship, as the altitude increases, the air density decreases. This is evident at extreme elevations such as that of Mount Everest, which peaks at approximately 8,828 meters above sea level and has an air density of 0.023 kilograms per cubic meter.
In the context of the question, when compared to sea level altitude benchmarks such as 10,000 ft. (3,000 m), 5,000 ft. (1,500 m), 2,000 ft. (600 m), and 1,000 ft. (300 m), Quito's altitude of approximately 9,200 feet positions it considerably above sea level, aligning with option A) Above sea level.