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Apply: Earth's changing climate


Carbon dioxide (COA2) is the main greenhouse gas causing climate change. Humans began emitting large amounts of COA2 during the Industrial Revolution, a period of development that started in the mid-1700s.
The graph below shows COA2 levels in the atmosphere before and after the start of the Industrial Revolution. Levels are given in units of parts per million, or ppm. In this case, ppm refers to the number of COA2 particles per million particles of air.
A line graph is shown. The horizontal axis is labeled Year and goes from 1 to 2021. The vertical axis is labeled Carbon dioxide (parts per million) and goes from 240 to 420. The line starts at 1 at roughly 275 parts per million, hovers around 280 parts per million until the start of the Industrial Revolution, and then increases to roughly 415 parts per million at 2021.
By about how many ppm did COA2 levels rise between the start of the Industrial Revolution and 2021?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi