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Apply: Newton’s law of universal gravitation

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Two identical buckets of concrete are placed 550, start text, m, end text apart, and the resulting gravitational force between them is 1, point, 378, times, 10, start superscript, minus, 13, end superscript, start text, N, end text.
What is the mass of each bucket of concrete?
Write your answer using two significant figures.
  • 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
start text, k, g, end text