https://www.youtube.com/watch?v=l0h_-3M0Pso

What is the approximate composition of the Earth's atmosphere?

• 80% nitrogen, 20% oxygen, less than 1% other gases

• 90% nitrogen, 10% oxygen

• 70% nitrogen, 30% oxygen

• 50% nitrogen, 50% oxygen

What role did volcanic activity play in the Earth's early atmosphere?

• It produced a lot of oxygen

• It formed the oceans

• It cooled down the Earth

• It created a carbon dioxide-rich atmosphere

What process is responsible for the decrease of carbon dioxide and increase of oxygen in the atmosphere?

• Photosynthesis

• Respiration

• Evaporation

• Condensation

What is the significance of algae and plants in the Earth's atmosphere?

• They decrease the oxygen levels

• They decrease carbon dioxide and increase oxygen through photosynthesis

• They produce carbon dioxide

• They increase the nitrogen levels

What happens to the carbon in plants and algae when they die?

• It evaporates into the atmosphere

• It becomes compressed into sedimentary rock, oil, and gas

• It turns into oxygen

• It dissolves in the ocean

What is crude oil and natural gas mainly formed from?

• Volcanic materials

• Dead plankton

• Dead land animals

• Living plants

What type of sedimentary rock is coal?

• Made from volcanic ash

• Made from dead plant material

• Made from animal bones

• Made from plastic waste

What is limestone primarily composed of?

• Dead insects

• Calcium carbonate from marine organisms

• Silicon dioxide

• Plastic debris

How long ago did algae and green plants start to evolve?

• About 2.7 billion years ago

• About 1 million years ago

• About 100,000 years ago

• About 4.6 billion years ago

What is the current theory about the Earth's atmosphere evolution based on?

• Complete certainty without any doubt

• Pure speculation

• Lots of evidence but still considered a theory

• A single piece of evidence