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Pre-calc Questions Concerning dB & Doubling Period

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Please help me with these 2 pre-calculus questions.

1) The drilling of a jackhammer was measured at 132 dB. The sound of whispering was measured at 28 dB. Find the ratio of the intensity of the drilling to that of the whispering.

2) A culture contains 10,000 bacteria initially. After an hour the bacteria count is 25,000.
a. Find the doubling period.
b. Find the number of the bacteria after 3 hours.

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Solution Summary

The double period of a bacteria culture is determined.

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