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AP®︎/College Environmental science

Course: AP®︎/College Environmental science > Unit 2

Lesson 3: Human populations
Science
AP®︎/College Environmental science
Populations
Human populations
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Human populations

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Problem

Scientists use the rule of 70 to calculate human population growth.
According to the rule of 70, what is the doubling time for a nation with a population growth rate of 2, percent per year?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
years
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