Why is it important to reduce soil erosion

Nuclear experimentation is a major global issue that affects relationships between countries. describe why countries try to limit the testing of nuclear weapons.

Can someone me choose a broad topic and area of focus i am really doing this as a tally to see which one most people pick ok water pollution global warming endangered species atmosphere for the !

Solve for r in the formula v = ir, when i = 5 and v = 15.