The typical pitch of a vuvuzela is said to be B flat below middle C.

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The surface of the hepatitis C protease turned out to be flat.

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The C-Max's fold-flat rear-seat system is brilliant, and rear cabin access is about as good as anything on the market.

WSJ: 2013 Ford C-Max Hybrid Review: A Fine Car Falls Way Short on MPG | Rumble Seat by Dan Neil

One reason is that the flat geometry of the hepatitis C protease protein made it is difficult target to hit with small-chemical drugs.

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In Jacob van Ruisdael's captivating "View of Haarlem" (c. 1670-75), a totally flat, almost totally dark landscape lies under a canvas that is two-thirds billowing, sky-broken clouds.

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