How are the semicircle and the diameter of a circle related?

A semicircle is half a circle so the diameter of a semicircle is half of which of a regular circle.

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.  

answer: 10 meter

step-by-step explanation:

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