Given the nucleotide sequences below, what type of mutation has occurred?

Before: A C C G T A T G T C A T

After: A C C G T A A G T C A T

A) deletion

B) insertion

C) mixer

D) substitution

Why might surface mining be less risky for miners than underground mining? a. surface miners can become trapped in a collapsed mine. b. surface miners work in dusty, enclosed areas. c. surface miners work aboveground. d. surface miners use elevators to enter mines.

In what for do plants utilize nitrogen? why do they need nitrogen?

20. in humans, freckles are dominant to no freckles. trey has no freckles and his wife anna grace has freckles, but her dad doesn't. they want to know what percentage of their kids would look like trey. show a punnett square to support your answer.