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.
Answer:
The stratification of Earth into its geologic layers was brought about by the formation of the Earth's iron core. The iron core was generated by a combination of radioactive decay and gravitation, which raised the temperature enough for molten iron to form.
Explanation:
F1 stands for first filial (daughter) generation
<span>F2 stands for second filial (daughter) generation</span>
I believe it is the nucleus.
Answer:
Is an animal that can be dependent or able to get internal generation from heat. So basically a warm blooded animal.
