Radioactive isotopes can be used in studies of metabolic pathways because

Select all of the statements which are true. electrons are located in shells or orbits around the atom. electrons orbit slowly around the atom. electrons travel in one flat path around the nucleus of an atom. the valence of an atom is determined by the number of electrons in the atom's outermost shell.

Which of two curves exhibits exponential growth

This statement about matter and its behavior is best classified as a