A.It eventually turns into heat.
B.It is used in a variety of forms.
C.Its use is chiefly responsible for air pollution.
D.Part of it is lost in the process of transmission.
A.When it is used in rural areas.
B.When it is environment-friendly.
C.When it operates at near capacity.
D.When it operates at regular times.
A.Traffic jams in cities.
B.Inefficient use of energy.
C.Fuel shortage.
D.Global warming