Where are conflicts between state and federal laws settled?

The Supremacy Clause is a clause within Article VI of the U.S. Constitution which dictates that federal law is the "supreme law of the land." This means that judges in every state must follow the Constitution, laws, and treaties of the federal government in matters which are directly or indirectly within the government's control.

Explanation:

a. poison gas was sprayed over battlefields by airplanes to weaken enemy positions before major attacks.