Answer: its CO2 for the first one
Explanation:
The answer is scrotal elevation. Hope this helps please help me by saying this is the brainiest.
I think DeniceSandidge. DNA is made up of molecules known as nucleotide, which are the building block s of nucleic acid. Each nucleotide compose of pentose sugar, phosphate group and four nitrogenous base. The four types of nitrogenous bases found in nucleotide are adenine, guanine, thymine and cytosine hope this helps pls thank me