Using rounding and scientific notation, it is found that the best estimate of 866,214,000,000 is:
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The number is 866,214,000,000.First, we round it. The second digit is 6 > 5, thus, we add one to the first digit, 1 + 8 = 9, and the rounded estimate for the number is: 900,000,000,000.After the 9, the number has 11 zeros, which means that in scientific notation, the estimate is given by:
Which is the first option.
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