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

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

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

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

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

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

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

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

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

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