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A Celsius and a Fahrenheit thermometer are placed in boiling water, then the water is cooled until the Fahrenheit reads 140 deg. By how much does the Celsius reading fall?

1. 30 deg
2. 40 deg
3. 60 deg
4. 80 deg

Correct answer: 40 deg

Solution

140 F = (140 - 32)*5/9 = 60 C; fall = 100 - 60 = 40 deg.

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