Answer:
D. Lots of vegetation
Explanation:
Urban heat islands form when cities replace natural land cover with dense concentrations of heat-absorbing pavement, buildings, and other surfaces. This has the impact of raising energy prices (for example, air conditioning), air pollution levels, and heat-related sickness and mortality.
45 guanine, 55 adenines
Every cytosine needs a guanine to be a pair, so that is 45 pairs right there.
100-45 = 55
There should be 55 adenine and thymine pairs to fill in the remaining bases
Answer:

point mutation, change within a gene in which one base pair in the DNA sequence is altered. Point mutations are frequently the result of mistakes made during DNA replication, although modification of DNA, such as through exposure to X-rays or to ultraviolet radiation, also can induce point mutations