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

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

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) Magnetic Field
D) Temperature

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

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

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

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

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

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