What did the Neutrality Act of 1939 allow other
countries to do?

He invoked the Neutrality Act, making sure neither Germany and Japan nor Britain and France, could buy anything from the U.S. When Poland was invaded, though, Congress changed its mind. The Neutrality Act of 1939 again allowed the U.S. to sell war materials to warring nations on a cash and carry basis.

a)the court decides which cases it will hear

well they usually trade goods for money. they mostly trade goods with other nations