Anyone know how to answer this?

Answer:
i metal
ii nonmetal
iii metal
iv nonmetal
Explanation:
If you look up what the element of a heater is, you get a picture of some sort of rod. It's the heating element of the heater, and must be some type of metal to conduct electricity and warm up. Fishing rods are made of either fiberglass, graphite, or carbon fibre. These are nonmetals. In order for a lightning rod to conduct electricity and bring the lightning down to the ground, it has to be metal. You wouldn't want a metal oven mitt, as that would burn your hand.