Scientists have found that the carbon-14 content of an unknown prehistoric sample was reduced to one-half. what best describes the identity of the sample?

Photosynthesis converts light energy to chemical energy. which molecules are the end product of this transformation of energy in this reaction?

What is the difference between an igneous, sedimentary and metamorphic rock

Food webs - transferring energy and matter from one level to another. here you see four food webs. one or more are incorrect. which food web(s) show the correct sequence of organisms, from start to top level consumer? a) a b) d c) c d) a and d