Answer:
Carbon
Explanation:
Carbon is a fundamental element in all living things.
Answer: D
Explanation: I got it right on the test
<u>Critical</u><u> </u><u>angle</u><u> </u><u>is</u><u> </u><u>2</u><u>4</u><u>.</u><u>4</u><u>°</u>
n is refractive index
c is critical angle
5/4 3.6