GRADE (9) CHAPTER 2 - LESSON 1

What is the primary source of all energy on Earth?

• The moon

• The sun

• The core

• The atmosphere

How long does it take Earth to complete one rotation on its axis?

• 365 days

• 24 hours

• 28 days

• 12 hours

Which of the following is NOT one of Earth's layers?

• Core

• Mantle

• Crust

• Troposphere

What is the approximate thickness of Earth's crust under mountains?

• 2 miles

• 8 miles

• 30 miles

• 75 miles

What percentage of Earth's surface is covered by water?

• 29%

• 50%

• 71%

• 90%

Which of the following is NOT part of Earth's physical systems?

• Hydrosphere

• Lithosphere

• Magnetosphere

• Biosphere

What is the primary gas in Earth's atmosphere?

• Oxygen

• Carbon dioxide

• Nitrogen

• Hydrogen

How many degrees is Earth tilted on its axis?

• 15.5 degrees

• 23.5 degrees

• 30 degrees

• 45 degrees

When is the summer solstice in the Northern Hemisphere?

• March 21

• June 21

• September 23

• December 22

What causes the seasons on Earth?

• Earth's rotation

• Earth's revolution around the sun

• Earth's tilt and revolution

• The moon's gravitational pull