$\"\"$

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The temperature in degrees Fahrenheit in a house is $\"\"$ ,

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where $\"\"$ is time in hours.

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$\"\"$ representing mid night.

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The hourly cost of cooling a house is $\"\"$ per degree.

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(a) Find the cost $\"\"$ of cooling the house if its thermostat is set at $\"\"$ by evaluating the integral $\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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The cost $\"\"$ of cooling the house if its thermostat is set at $\"\"$ is $\"\"$ .

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$\"\"$

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(b) Find the savings from resetting the thermostat to $\"\"$ by evaluating the integral $\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ \ \

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$ . $\"\"$

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(a) The cost $\"\"$ of cooling the house if its thermostat is set at $\"\"$ is $\"\"$ .

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(b) the savings from resetting the thermostat to $\"\"$ is $\"\"$ .