How do you convert from milli to micro

In what for do plants utilize nitrogen? why do they need nitrogen?

The carbon cycle is best defined as a process in which a. carbon changes from inorganic forms to organic forms and back b. carbon is changed into other elements such as oxygen or nitrogen c. carbon is continually created from the sun’s energy by plants d. carbon is consumed and regenerated from other elements such as oxygen and nitrogen

Compare the parts of a cell and the cell as a whole to another common nonliving system (i. e., a car, a city, describe the parts of a cell and their primary function.