A: transformers work with either ac or dc electricity. true/false
b: power companies use high voltages to reduce power loss over long transmission distances. true/false
c: a(n) uses electromagnetic induction to increase or decrease voltage.
d: materials that lose all electrical resistance at low temperatures are known as and are ideal for constructing powerful electromagnets.
e: an electric device that uses an electromagnet to open and close a switch is a(n)