Would the control group not receive the treatment, or receive the same treatment that has been used before?

The many volcanoes located along the edge of the pacific ocean make up the ring of fire. how does subduction play a role in the volcanic activity in the ring of fire?

Melting glaciers is a serious threat to the environment what is the possible consequence of melting glaciers on polar bears?

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity