1. Why has the percentage of hydrogen decreased from the early atmosphere to now?
- It has been trapped underground
- Human activity
- It's escaped from the atompshere
- It dissolved in oceans and rivers
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Other questions in this quiz
2. Why does the rate of photosynthesis increase in the summer?
- Longer day hours and increased rainfall
- Longer day hours and hotter weather
- Shorter day hours and hotter weather
- Shorter day hours and decreased rainfall
3. What percentage, on average, of the air is nitrogen?
4. Which of these gases is created using UV radiation?
- Carbon Monoxide
- Sulphur Dioxide
5. How does nitrogen support life?
- Used in respiration
- Blocks harmful UV rays
- Used as nutrients for plants
- Used in photosynthesis