Which of the following is the best description of natural selection? The struggle to exist.
The change in variation of a species.
Survival of the fittest.
Overproduction of offspring.

Mercury metal is poured into a graduated cylinder that holds exactly 22.5 ml the mercury used to fill the cylinder mass in 306.0 g from this information calculate the density of mercury

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium