How enzyme works like a lock and key

Which mantle is under the crust the upper mantle or the lower mantle i think it's upper let me know if i'm right

There are six elements that make up most of the human body. which of the following is not one of these six elements?

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