Part D: The idea of molecular clock genes has been studied for decades, but the hypothesis remains a controversial topic in evolutionary biology. Why do you think that is the case? What are three questions you still have about the use of molecular clocks?

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)

c

explanation:

not sure if this is what you'r looking for eubacteria and archaebacteria