A. Natural Selection. This is because the weeds that are not resistant to it die out before they can reproduce, but the resistant ones grow to maturity and then reproduce, passing down the resistance gene. Over time, the resistance gene would become a normal thing in weeds, while the non-resistant gene would not exist anyone, since the gene could not be passed on.
Answer:
32%
Explanation:
According to Chargaff in his complementary base pairing rule, he stated that the proportion of purine and pyrimidine bases is equal to 100%
That is, A + T + G + C = 100%
Where A=T and G=C i.e the proportion of each base pair is equal.
Hence, if the Guanine content is 18%, it means the Cytosine content of that DNA molecule must also be 18%. Therefore:
18 + 18 + A + T = 100
A + T = 100 - 36
A + T = 64
If the sum proportion of Adenine and Thymine is 64% and each must contain equal proportions, A or T = 64/2 = 32
Hence, Adenine contains 32%, likewise Thymine.
Mitosis should be the answer. if not that, then cell division. hope this helps :3