Proteins serve a variety of functions in living organisms. which of the following protein-containing substances plays a role in defense?
choices:
muscles
hair
antibodies
hormones

it cools slower in the earth meaning the crystals have more time to form than lava on the surface

substitution is the answer in this case

the atmospheric gas that forms a mild acid when dissolved in water is called carbon dioxide. the correct answer is a. 2.) chemical weathering would cause an inscription on a marble headstone to become harder and harder to read over time.