Which of the following best explains why deforestation increases the risk of floods in an area?
a. tree leaves catch and retain rain water.
b. trees block the free flow of water.
c. deforestation increases precipitation.
d. tree roots improve soil water retention. select the best answer from the choices provided a b c d

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.

Why does the earth spin slowly, not faster? is it possible to prove it scientifically? can you prove it with math?

Which of the following is not a benefit of genetically modified foods? a. pest-resistant crops b. herbicide-resistant crops c. plants that do not require water?