$\"\"$

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(a)

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The level of sound formula $\"\"$ .

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The initial intensity value, $\"\"$ watt per square meter.

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Rustle of leaves of intensity, $\"\"$ watt per square meter.

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Consider $\"\"$ .

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Substitute values of $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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The level of sound $\"\"$ .

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$\"\"$

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(b)

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The level of sound formula $\"\"$ . \ \

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Consider $\"\"$ . \ \

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Substitute values of $\"\"$ .

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$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$ . \ \ The level of sound $\"\"$ . $\"\"$

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(c)

\

The level of sound formula $\"\"$ .

\

Consider $\"\"$ .

\

Substitute values of $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$ . \ \ The level of sound $\"\"$ . $\"\"$

\

(d)

\

The level of sound formula $\"\"$ .

\

Consider $\"\"$ .

\

Substitute values of $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$ .

\

The level of sound $\"\"$ .

\

$\"\"$

\

(a) The level of sound $\"\"$ .

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(b) The level of sound $\"\"$ .

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(c) The level of sound $\"\"$ .

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(d) The level of sound $\"\"$ .