Answer:
nitrogen
Explanation:
because I also had this in exam and I was correct
An electromagnet is a device that sends electricity through a coil of wire to produce a magnetic field. This leads to a magnet that can be controlled - turned on and off with the flip of a switch, or increased or decreased in strength. The coils are often wrapped around a regular magnet to make it stronger.
A ball hit by a man is stronger than a ball hit by a man because the man uses more force when hitting the ball than the boy does.
