It is a Chemical reaction taking place un a solution in which one or more of the products is insoluble in the solvent, and so forms solid particles that fall to the bottom of the reactor
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.
Carbon dioxide + water -> glucose and oxygen
So, the answer would he 'A carbon dioxide and water combine and produce sugar and oxygen'.
Hope this helps! :)
Answer;
-Francis Galton
Explanation;
-This phrase was popularized by Francis Galton in discussion of the influences on social development. The two to first bring the argument to light may have been Locke and Rene Descartes, when Locke proposed that people are born without any innate ideas.
-The nature vs. nurture hypothesis is a scientific, cultural, and philosophical debate about whether human culture, behavior, and personality are caused primarily by nature or nurture.