True/false
50% of the earth's atmosphere (total mass) is below 30km (19mi) from the surface.

False

Explanation:

solution

when we move upward from ground, there some layer we divided in atmosphere there name is as troposphere, stratosphere, mesosphere, thermosphere and exosphere

and here lowest layer of our atmosphere is troposphere and it is extend upto  10km or 6.2 miles

but 50 percent of total mass of atmosphere is located in troposphere in about 5 to 6 km or 3.1 to 3.7 miles

so given statement is false

mercury

explanation:

mercury is the least dense because of its size

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