Answer:
A major factor in determining the mode of nitrogen excretion is the availability of water in the environment. Generally, aquatic animals excrete mostly ammonia, whereas terrestrial animals excrete either urea or uric acid.
Explanation:
Sorry but. Do your own school!
The troposphere is shallowest or narrowest at the poles, and deepest or thickest at the equator. At the geographic North and South Poles, the troposphere reaches only 4 miles high, while at the equator, it extends nearly 12 miles high.