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解析:TheAerospaceBicycle That Fell toE

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【单选题】

TheAerospaceBicycle That Fell toEarth
A、radical new bicycle had its first public showing at the NationalBritishCyclingChampionships in Shrewsbury last weeken
D、Based on the gold medal-winning design from theBarcelona Olympics, it is the first commercial mountain bike made of a single piece of carbon fibre.
Bicycles for amateurs have up to now been made of steel, aluminum or magnesium tubes welded together into the conventional "A-frame"shape.But last year, theBritish competitorChrisBoardman set world records while winning titles in the Olympic cycling pursuit events on a custom built, carbon-fibre bicycle with lower weight and wind resistance than standard models.Because carbon fibre is both light and extremely strong, it does not need theA-frame shape, saving further weight.Carbon fibre can also be moulded in a single piece, avoiding the weakness of welds.
The new bike, which will cost between $ 2000 and $ 3000 when it reaches the shops next month, has the same advantages as the Olympic model. It weighs about 11 kilograms,a saving of 1.5 kilograms on metal frames. With no crossbar, it has a lower center of gravity, making it easier to use in race conditions. "When you’re doing some aggressive riding,you throw the bike about from side to side," explainsEddieEccleston, director ofBritishEagle, aBritish bicycle manufacturer based in Powys, Wales, which is marketing the bikes. "The low centre of gravity gives you better control. "
The frames are being made in the U. S. forBritishEagle by SP systems inCamarillo,California, which has clients in the aerospace industry, "This is aerospace technology brought into cycling by enthusiasts", saysEccleston. When professionals tested racing versions of the bike before the Tour de France, they were quicker than metal versions by up to 3 seconds per kilometer.
The new design has no struts between the saddle and the back wheel; instead, the frame’s flexibility can be "tuned" to individual tastes by changing the mixture of Kevlar fibre and carbon fibre in the back wheel strut, allowing up to 5 centimeters of movement.
The carbon-fibre design has a lower centre of gravity and smoother back-wheel suspension than conventional bikes.
According to the context, "bicycles for amateurs" at the beginning of the second paragraph refers to bicycles______.A.that people buy only for riding in their daily life

B、that are bought by amateur cyclists who like cycling as an exercise
C.that are built for customers in general

D、that non-Olympic competitors use

网考网参考答案:C
网考网解析:

[解析] 本题的四个选项中,只有C项为正确答案。这从文中第二段的"On a custom-built"可以推知,即自行车是定做的。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>

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