$\"\"$

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The initial temperature of the cool drink is $\"\"$ .

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Room temperature is $\"\"$ .

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After $\"\"$ minutes temperature increased to $\"\"$ then $\"\"$ .

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Newton $\"\"$ s Law of Cooling : $\"\"$ .

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The change in temperature : $\"\"$ .

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Here $\"\"$ is the temperature of the cool drink and $\"\"$ is the surrondings temperatuture.

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At the intital time : $\"\"$ .

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$\"\"$ .

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The general equation is $\"\"$ .

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Temperature of the cool drink at time $\"\"$ is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the equation $\"\"$ .

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$\"\"$ .

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Temperature of the cool drink at time $\"\"$ minutes is $\"\"$ .

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Substitute $\"\"$ in the above equation.

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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Find the temperature after $\"\"$ minutes.

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Temperature of the cool drink at time $\"\"$ is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the above equation.

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$\"\"$

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$\"\"$

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$\"\"$

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Substitute $\"\"$ in the equation $\"\"$ .

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$\"\"$

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The temperature after $\"\"$ minutes is $\"\"$ .

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$\"\"$

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(b).

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Find the time when the temperature is $\"\"$ .

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$\"\"$ .

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$\"\"$

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The temperature is $\"\"$ after $\"\"$ minutes.

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$\"\"$

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(a) The temperature after $\"\"$ minutes is $\"\"$ .

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(b) The temperature is $\"\"$ after $\"\"$ minutes.