The main advantage of solar energy is: a. it is low in cost. b. it can be used all the time. c. it has very little pollution. d. it is free.

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils

Plants consume most of their carbon from a. the soil b. the water c. the roots d. the air

Describe the layers of the suns atmosphere?