The principle that states that national laws will be followed if state laws conflict with them is found in the commerce clause.

In a __________, virtually all power goes to the national government

A) confederal system B) federal system C) unitary system D) self-government system E) regional system

Which of the following are forms of pollution that affect Earth’s outermost layers of atmosphere?

a. Destruction of the ozone layer b. Smog and acid rain c. River and ocean pollution d. Contamination with greenhouse gases