This is a spherical mixture of gases that surrounds the planets

a. exosphere
b. atmosphere
c. lithosphere
d. troposphere

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

and after water is usually warmed by the sun the water temperature raises and then evaporates .