Sulfur is a non-metal I can tell because it's a insulator that means it doesn't allow heat or electricity to travel easily threw it. I has a no luster, it looks dull. It is not magnetic either.
Baron is not a metal or non-metal it's a metalloid. Baron is a metalloid because it can be can have a shinny or dull luster. It can conduct electricity and heat but not as well as metals and, it's malleable.