Scientists analyzed ice cores from Antarctica and measured trapped air bubbles from different time periods. The graph showed CO₂ concentration was 280 ppm in 1850 and 415 ppm in 2020. What is the percentage increase in atmospheric CO₂ concentration?

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Question

Scientists analyzed ice cores from Antarctica and measured trapped air bubbles from different time periods. The graph showed CO₂ concentration was 280 ppm in 1850 and 415 ppm in 2020. What is the percentage increase in atmospheric CO₂ concentration?

Accepted Answer

48% — Award 1 mark for B. Calculation: (415-280)/280 × 100 = 135/280 × 100 = 48.2%. A is incorrect due to calculation error. C incorrectly calculates (415-280)/415 × 100. D incorrectly gives the value of 135 without dividing by the original value.

Answer

32%

Answer

68%

Answer

48%

Answer

135%

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