A student conducted a comparative investigation to test the hypothesis that different areas of New York City have different levels of air pollution. Which is a likely benefit of this comparative investigation? O It provides her with a large amount of information about air pollution in New York City. O It provides her with results that are valid for a long time. It requires that she observe a limited number variables. It allows her to learn about the causes and effects of air pollution in major cities.​

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

the answer is b & c i believe : )

b. examine and describe cells

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.