The greenhouse effect occurs when rays enter our atmosphere and are reflected from the ground up. They get changed during their voyage through our atmosphere and they change in such a way that they can't leave the atmosphere anymore. Then they stay inside and heat up the planet which causes thing like global warming. That's what the greenhouse effect is.
The control group is the part of an experiment that does not receive the variable and is used for comparison.
In Newton's Third Law of Motion, when one object exerts a force on a second object, the forces are equal in magnitude and opposite in direction. The correct answer is B.
The main difference between prokaryotes and eukaryotes is the presence of nucleus in eukaryotes and its absence in prokaryotes. Also, prokaryotes are unicellular, so one cell is a whole organism. On the other hand, eukaryotes are mainly multicellular, and thus more complex. More complex DNA is inside the nucleus in the eukaryotes which enables them to conduct a wider range of functions. Prokaryotes, as a single cell, have simple functions present.