$\"\"$

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The Humber bridge has main span is $\"\"$ .

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The height of the towers is $\"\"$ .

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Find the arc length of the cable.

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From exercise (69):

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The arc length of the cable is $\"\"$ .

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

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$\"\"$ .

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Consider the function $\"\"$ .

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Graph the function $\"\"$ on $\"\"$ .

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$\"\"$

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Observe the graph:

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$\"\"$ .

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Therefore, $\"\"$ .

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The arc length of the cable is $\"\"$ .

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$\"\"$

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The arc length of the cable is $\"\"$ .