A) An automobile that operates on fuel cells
B) A wood burning stove
C) A gasoline burning automobile
D) A coal burning generator

A) The moon
B) Running water
C) The sun
D) Heat from within the Earth's crust

A) The number of clouds in the sky
B) The speed of the wind
C) The state of the atmosphere at any particular time
D) The amount of moisture in the air

A) Atmosphere
B) Rotation
C) Temperature
D) Magnetic Field

A) The sun powers life on Earth
B) The sun causes plants to wither and die
C) The sun protects life on Earth
D) The sun damages life on Earth

A) The Earth's changing distance from the sun
B) The tilt of the Earth on it's axis
C) Changes in the sun's intensity
D) The Earth's rotation

A) Because it reflects sunlight
B) It makes it's own light
C) It reflects light from Earth
D) It reflects light from stars

A) Mountains
B) Sunken plains, or seas
C) High plateaus
D) Deep craters

A) Motion
B) Light
C) Heat
D) Electricity

A) Lift and thrust
B) Motion and time
C) Wind and rain
D) Temperature and pressure