The correct answer is - D) covered by warm shallow seas.
The fact that the crinoids are have an abundance in the fossil records in Pennsylvania in the Mississippian Period, tells us that this area was covered with shallow and warm seas. The reason why we can get that conclusion is that the crinoids live only in that kind of environment, so it simply a logical conclusion.
The geological data is also confirming this, as it is easily noticeable in the layers that during this period of the geologic past, what is now Pennsylvania, was covered with shallow sea waters. Also, this waters were warm too, as the climate was warm and humid and that period, so it was a perfect environment for the crinoids to flourish.
I think your anwser would be all of the above but you don't have it
Answer:d.
Explanation:hope you guys got it that’s what I got and it was right
Answer:
α = 0 if β= 0
Explanation:
If both species want to persist in the same environment and their niches are also over lapping then both of the co-efficient values should be equal. There are two possibilities on these values for persistence. One is that one should compromise to the change produced by the invasive specie and two is that the new specie should compromise if he wants to stay (<em><u>Assuming that there is no competition</u></em>). In this way their niches won't overlap to a greater extent and therefore better chances of survival for both.
It also plays a key role in shaping organic molecules. Carbon<span> is very </span>important<span> to the chemistry of living things, mainly because of the versatility of structures it can form with itself and with other atoms</span>