Tidal energy can be used to produce electricity.
Tidal energy is one of the oldest forms of energy used by humans.
One of the oldest forms of energy used by humans can be used to produce electricity.
One of the oldest forms of energy used by humans can be used to produce what?
(a) food
(b) engines
(c) waves
(d) chemicals
(e) Decibels
(f) sound
(g) energy
(h) hormones