Answer:
B) 21% D) they fall to earth as rain, precipitation
Explanation:
How much oxygen is contained in the atmosphere?
Oxygen is the second largely present gas in our atmosphere. The amount of oxygen in our atmosphere is 20.95% which is about 21%.
B) 21%
Clouds are made up of tiny droplets. What happens to the droplets when they are very heavy?
When the droplets agglomerate by sticking to each other, they become heavy.
When they become too heavy they can not stay in the atmosphere as the gravity pulls them down to fall on earth as rain.
When the droplets are tiny, the effect of air current plays the major role, when the droplets are heavy, the gravity plays the major role.
D) they fall to earth as rain, precipitation.
