Hello!
To find the increase in depth, we must subtract the initial depth from the final depth. This can can be represented by the following formula:
(change in depth) = (final depth) – (initial depth)
Insert any known values into the equation above and simplify:
(change in depth) =
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–
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change in depth =
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We have now proven the change in depth to equal
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. We know, however, that this fraction can be reduced to a value of
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. Therefore,
the answer to this problem is C.
I hope this helps!