Is the political scientist and author of Democracy in America. He believed that the delegation of government to the states was one of the strong points of the American system.

Tolerance to high levels of salinity

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .

The answer is b because c don't explain why the moths are on them and it isn't a because as we know only one species of moth does this