Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project?

Rob spent 25% extra percent on his project than the had planned.

Let us assume total number of hours spent x hours.

Given that he spent an extra h hours on the project

So, we could say 25% of x is h.

0.25 x = h.

Dividing both sides by 0.25.

We get 0.25h/0.25 = h/0.25.

x = h/0.25.

Let us convert 0.25 into fractions.

0.25 = 25/100 = 1/4.

Therefore,

x = h/1/4 = 4h.

Therefore, Rob planned 4h hours.

He spent h hours extra.

So, he spent total 4h+h = 5h hours total.

the answer is; biodiversity resulting from few ancestors

adaptive radiation occurs when a population is subjected to a large natural environment with spatial ecological variations. the parts of the population in the different ecologies begin to adapt to their local environments. due to non-random mating across the large populations, this causes the different populations from the large population to speciate within their local environments. they, therefore, diverge to different species sharing a common ancestor.  

i believe it's a.

i'm not sure on this one, most likely correct.