At a fabric store, they can cut a length of fabric off a big roll, so you can buy any length you like. the cost for 3 feet of silk fabric is $9.75. how much would you pay for 20 feet of silk fabric, at this rate?

$65

Step-by-step explanation:

9.75/3=3.25

3.25*20=65

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.