Which of the following drives the movement of convection currents

a.pressure differences
b.density differences
c.volume differences


Which of the following are considered alternative energy sources?

a.fossil fuels, nuclear, geothermal
b.solar, wind, hydropower
c.coal, oil, and natural gas
d.solar, wind, natural gas

Why is it important for humans to take advantage of alternative energy sources?

a.Alternative energy is cheaper than fossil fuels.
b.None of the alternative energy sources pollutes the environment.
c.Fossil fuels are in limited supply and alternative energy sources will replace them.

The energy of motion is called heat energy.

a.True
b.False

A
B
C
B (it's friction which creates heat energy)

B
B
C
B kinetic energy is the energy of motion