Can anyone me with this biology question? d: carbon dioxide and oxygen

Select the correct answer. which term do biologists use to describe the average number of individuals of a species per unit area? a. carrying capacity b. population density c. minimal viable population d. survivability curve

Which are reasons cells undergo cell division?

1. which of the following transport mechanisms utilizes energy? a. osmosis b. diffusion c. facilitated diffusion d. endocytosis