13. rich is driving from philadelphia to pittsburgh at 70 mph and michelle is driving from pittsburgh to philadelphia at 65 mph. if philadelphia and pittsburgh are 305 miles apart how long will it take rich and michelle to meet?

2.26 hours

Step-by-step explanation:

Given

Rich is driving from Philadelphia to Pittsburgh at 70 mph

and Michelle speed is 65 mph

If Philadelphia and  Pittsburgh is 305 miles apart

Let Rich travels x miles in t time

therefore

Michelle travels 305 -x

27x=4270

time taken t 2.26 hours

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.  

47.28 or 47.2857143

step-by-step explanation:

you just divide 331 by 7 and you get that answer. ( i think so tho)