When scientists compare molecular clocks between species, they have to use the same segment of DNA. Which of these statements would explain why that is necessary?

If you are in a chronic state of anxiety but also suffer from moment of sudden, intense fear you are problably suffering. from

6. in domesticated cats, the following are independently assorting: normal ears (t) is dominant to tufted ears (t); curved whiskers (c) is dominant to straight whiskers (c); the presence of six toes (s) is dominant to five toes (s); gene for hair length is an x-linked codominant. the three phenotypes for hair length are long (xhxh), medium (xhxh), and short (xhxh); medium is the heterozygous condition. given two parents: ttccssxhxh x ttccssxhy how many different gametes could be formed in the female cat with respect to these four traits? how many phenotypes are possible in the offspring from this mating?

In which state was more than 100 billion tons of coal mined in 2005?