Where Did the Oxygen Go?
Questions
1. Use context clues in the second paragraph to write your own definition of the word photosynthesis.
2. Compare and Contrast How are gases from underwater volcanoes different than gases from volcanoes on land?
Math Concepts
3. The numbers below show one billion and one million.
1 billion = 1,000,000,000
1 million = 1,000,000
a. Write out 2.7 billion and 2.5 billion using numbers.
b. Subtract 2.5 billion from 2.7 billion. Show your work.
In Your Journal
Write a short story about what Earth was like 2-3 billion years ago. Use the information in the article to get ideas about what was happening on Earth during that time. Think about what was living on Earth, what the air was like, and how volcanoes affected Earth's surface. Use your imagination to write the narration.