An alien has a mass of 75 kg and weighs 225 N. What is the acceleration due to gravity on the alien's home planet? Don't forget units! *

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.

An ecologist is studying the effects that a population of predators is having on a population of a prey. he used data from the field to produce this graph. which conclusion can draw from the graph?

Which greenhouse gas is emitted when burn fossil fuels for energy? a.nitrogen b.oxygen c.carbon dioxide d.helium