You never see them, but they’re with you every time you fly. They record where you’re going, how fast you’re traveling and wheth

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问题     You never see them, but they’re with you every time you fly. They record where you’re going, how fast you’re traveling and whether everything on your airplane is functioning normally. Their ability to withstand almost any disaster makes them seem like something out of a comic book. They’re known as the black box.
    When planes fall from the sky, as a Yemeni airliner did on its way to the Comoros Islands in the Indian Ocean June 30, 2009, the black box is the best bet for identifying what went wrong. So when a French submarine (潜水艇) detected the device’s homing signal five days later, the discovery marked a huge step toward determining the cause of a tragedy in which 152 passengers were killed.
    In 1958, Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first model for a black box, which became a requirement on all U. S. commercial flights by 1960. Early models often failed to withstand crashes, however, so in 1965 the device was completely redesigned and moved to the rear of the plane—the area least subject to impact—from its original position in the landing wells (起落架舱). That same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to aid visibility.
    Modern airplanes have two black boxes:  a voice recorder, which tracks pilots’ conversations, and, a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help investigators reconstruct the aircraft’s final moments. Placed in an insulated (隔绝的) case and surrounded by quarter-inch-thick panels of stainless steel, the boxes can withstand massive force and temperatures up to 2,000°F.  When submerged, they’re also able to emit signals from depths of 20,000 ft. Experts believe the boxes from Air France Flight 447, which crashed near Brazil on June 1, 2009, are in water nearly that deep, but statistics say they’re still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane’s black boxes were never recovered.

What does the author say about Michelle Obama as a First Lady?

选项 A、However many fans she has, she should remain modest.
B、She shouldn’t disappoint the African-American community.
C、However hard she tries, she can’t expect to please everybody.
D、She will give priority to African-American women’s concerns.

答案C

解析 细节题。根据题目定位到文中第三段最后一句That same year,the Federal Aviation Authority required that the boxes, which were never actually black,be painted orange or yellow to aid visibility. (同年。联邦航空局规定把这个从来都不是真正黑色的盒子涂成黄色以增加能见度.)可知,漆成黄色是为了容易辨认。选项A(与飞机颜色区分),及选项B(提醒人们小心处理),还有选项D(遵守国际规格),均不符合题意。因此选C。
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