What are the answer choices???
5-Ethyl-3,3,4-trimethylheptane has 3 secondary carbon. A primary carbon written as 1° is a carbon that has one carbon atom attached to it. A secondary carbon written as 2° is a carbon attached to two other carbons, while a tertiary carbon written as 3° is a carbon attached to three other carbons.
<span>Dmitri Mendeleev's Periodic Law states that chemical and physical properties repeat themselves in groups of 8.</span>
your answer would be C hope this helps
B.
The cynobacteria were already there without the oxygen, so that rules out A, and a lot of prokaryotes were anaerobic, so that rules out C. Finally, Photosynthesis does not require oxygen. Instead, Oxygen is a waste product of it. Therefore, it cannot be D. So, we are only left with B
Hoped this helped :D
