Answer: This may be wrong but I think it is 1 is c 2 is e 3 is d 4 is a and 5 is b
Explanation:
More oxygen becomes available in the water helping the marine or freshwater creatures live. <span />
Answer:
So where then did all the carbon that living organisms are built of come from? It turns out that most of the carbon we use today came from a collision with another smallish planet about 4.4 billion years ago.
That'll be guanine. If you look up "pyrimidine" in google, it will tell you the two nucleotides that are pyrmidines are cytosine and thymine. So that leaves guanine.
It is negative selection <span />
