Answer:
Our bodies consist of a number of biological systems that carry out specific functions necessary for everyday living. The job of the circulatory system is to move blood, nutrients, oxygen, carbon dioxide, and hormones, around the body. It consists of the heart, blood, blood vessels,arteries and veins.
Explanation:
Radon is a radioactive noble gas. It is really difficult to find it naturally since it does occur, but in really small quatities as it is a radioactive element, and therefore dacys.
Symbol: Rn
Atomic number: 86
Hope it helped,
BioTeacher101
<span>b. they may affect several populations in an ecosystem.
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