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:
Simple answer, yes.
Explanation:
Monocots have isobilateral leaf I.e both sides of the leaf are equally exposed to the sun.
Dicots have dorsiventral leaf I.e. ventral side is exposed to the sun more than the dorsal side.
They are very distinctly different from each other and can be separated easily, and so are their roots.
Answer:
changes in temperature that happen with increasing altitude.
- they are both found in the same place
- they are both passed down to newer generations
- both of them can determine your traits
Answer:Stars are formed in clouds of gas and dust, known as nebulae. Nuclear reactions at the centre (or core) of stars provides enough energy to make them shine brightly for many years. The exact lifetime of a star depends very much on its size.