Keiko treats a number of patients who live in a remote area of her state. She talks to them via a videoconferencing service. Keiko provides
to her patients.

What is the main difference between trace elements and the main elements that make up the body? 1) main elements consist of heavier atoms. 2) trace elements are only needed in small amounts. 3) trace elements consist of heavier atoms. 4) main elements are only needed in small amounts.