What are ways that human activity impacts the water supply?
creating sewage
spreading chemicals
increasing radioactivity
all of the above

Why learning about people and places around is important?

Which sentences describes a cycle of dependency? a. aid harms the local economy creating the need for more aid.b. aid improves infrastructure and creates more wealth and more good infrastructure.c. aid programs become more reliable over time so people can depend on them.d. no answer is correct

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?