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kairoshan
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diogoguitarrista
It is not a DS problem, but that's OK.

I understood by two ways:

1) U = 8d/hˆ2

U' = 8*2d/ (1/2*h)ˆ2 = 64d/hˆ2 --> U *64 = U ' --> 700% increase

Ans: D

2) U = 8d/(2h)

U '= 8*2d/(2*(1/2)*d) = 16d/h --> 300% increase

Ans A

OA is D. sorry. I just edited the question.
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In this problem why does it become \((64h^2)/h^2\) instead of \((32h^2)/h^2\)
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Bunuel
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hfbamafan
In this problem why does it become \((64h^2)/h^2\) instead of \((32h^2)/h^2\)

Check here: the-useful-life-of-a-certain-piece-of-equipment-is-determine-101496.html#p786365

Hope it helps.
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