Answer:
6 - iron
7 - by stringing many magnets together
Step-by-step explanation:
6 - substances such as iron, cobalt, and nickel, most of the electrons spin in the same direction. This makes the atoms in these substances strongly magnetic—but they are not yet magnets. ... The piece of iron has become a magnet. Some substances can be magnetized by an electric current.
7 - it is that only