Which action could be taken by an individual and would have the greatest positive impact on global consumption of nonrenewable resources? using only recycled materials in construction

using hydroelectric power instead of coal

using and recycling plastic water bottles

using less energy at home

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 .