The ozone layer of the Earth's atmosphere is what protects living things from too much ultraviolet radiation, if that's what you're asking about.
Answer: option A. 2
Explanation: in the formula Sr3(PO4)2, the 2 behind (PO4) is affecting both P and O4. It means that we have P2 in the formula
<u> C^1H^1C^1I^1</u>
Explanation:
<u>this seems already balanced</u>
C = 1
H =1
C = 1
I = 1
