Water that is dense will float while water that is less dense will sink.
True or false ?

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

19. scientists use meteorites that hit earth to provide evidence of the composition of earth's interior because they hypothesize that

How many years would it take the atlantic ocean to grow 500 centimeters? show your work.