$\"\"$

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The general formula of growth rate is $\"\"$ .

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(a)

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The intial mass $\"\"$ mg.

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Here represents the mass after $\"\"$ days.

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Mass remaining after $\"\"$ days is $\"\"$ .

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Find the value of $\"\"$ such that half life of strontium is $\"\"$ days.

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Consider $\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$ .

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$

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

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Mass remaining after $\"\"$ days is $\"\"$ .

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$\"\"$

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(b).

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Find the mass after $\"\"$ days.

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

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$\"\"$

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Mass remaining after $\"\"$ days is $\"\"$ mg.

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$\"\"$

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(c).

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Find time $\"\"$ when $\"\"$ mg.

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

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$\"\"$

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$\"\"$ days.

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Time required for the sample to decay to mass of $\"\"$ mg is $\"\"$ days.

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$\"\"$

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(d).

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Graph:

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Graph for the function $\"\"$ .

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$\"\"$

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$\"\"$

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(a) Mass remaining after $\"\"$ days is $\"\"$ .

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(b) Mass remaining after $\"\"$ days is $\"\"$ mg.

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(c) Time required for the sample to decay to mass of $\"\"$ mg is $\"\"$ days.

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(d)

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Graph of the function $\"\"$ .

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$\"\"$ .