$\"\"$

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The function is $\"\"$ , where $\"\"$ is the amount learned at time $\"\"$ ,The number $\"\"$ represents the amount to be learned ,the number $\"\"$ measures the rate of learning.

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(a)

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Find the rate of learning.

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Here, $\"\"$ , $\"\"$ and $\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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From the definition $\"x$ if and only if $\"y$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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The rate of learning is $\"\"$ .

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$\"\"$

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(b)

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Approximately how many words will the student have learned after $\"\"$ minutes.

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Therefore, $\"\"$ .

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Substitue $\"\"$ , $\"\"$ , $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Approximately $\"\"$ words will the student have learned after $\"\"$ minutes.

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$\"\"$

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(c)

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Approximately how many words will the student have learned after $\"\"$ minutes.

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Therefore, $\"\"$ .

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Substitue $\"\"$ , $\"\"$ , $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Approximately $\"\"$ words will the student have learned after $\"\"$ minutes.

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$\"\"$

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(d)

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How long does it take for the student to learn $\"\"$ words.

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Therefore, $\"\"$ .

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Substitue $\"\"$ , $\"\"$ , $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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From the definition $\"x$ if and only if $\"y$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Approximately $\"\"$ minutes will take the student will learn $\"\"$ words.

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$\"\"$

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(a) The rate of learning is $\"\"$ .

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(b) Approximately $\"\"$ words will the student have learned after $\"\"$ minutes.

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(c) Approximately $\"\"$ words will the student have learned after $\"\"$ minutes.

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(d) Approximately $\"\"$ minutes will take the student will learn $\"\"$ words.

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