Answer
a. Calcium and oxygen are abundant both in the human body and in Earth's crust, oceans, and atmosphere.
b. Aluminum, silicon, and iron are abundant in Earth's crust, oceans, and atmosphere, but not in the human body.
Work Step by Step
a. Calcium and oxygen are abundant both in the human body and in Earth's crust, oceans, and atmosphere.
b. Aluminum, silicon, and iron are abundant in Earth's crust, oceans, and atmosphere, but not in the human body.