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Nesterboy [21]
2 years ago
10

By the end of the day, a 45 ft x 25 ft x 8 ft office has a carbon dioxide air level of 1,100 ppm. Determine the time in hours ne

cessary to reduce this concentration to ambient levels (approximately 325 ppm) assuming 20% of the return is "fresh" makeup air and there are two air changes per hour.
Engineering
1 answer:
Julli [10]2 years ago
6 0

The total hours that are necessary to reduce carbon dioxide level to at least 325 ppm are 4 hours.

<h3>How does carbon dioxide concentration change over time?</h3>

First hour:

  • 1,100 - 20 %
  • 1,100 - 220 = 880

  • 880 - 20%
  • 880 - 176 = 704

Second hour:

  • 704 - 20%
  • 704 - 140.8 =663.2

  • 663.2 - 20%
  • 663.2 - 132.64 = 530.56

Third hour:

  • 530.56 - 20%
  • 530.56 - 106.112 = 424.44

  • 424.44 - 20%
  • 424.44 - 84.88 = 339.55

Fourth hour:

  • 339.55 - 20%
  • 339.55 - 67.91 = 271.64

Learn more about carbon dioxide in: brainly.com/question/3049557

#SPJ1

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