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 do many African-American women hope Michelle Obama will do?

选项 A、Help change the prevailing view about black women.
B、Help her husband in the task of changing America.
C、Outshine previous First Ladies.
D、Fully display her fine qualities.

答案A

解析 细节题。根据题目定位到文中最后一段倒数第二、三句When submerged。they’re also able to emit signals from depths of 20,000 ft.Experts believe the boxes from Air France F1ight 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.(即使沉入水中,它依然可以于2000英尺深的地方发射信号。专家相信2009年6月1日在巴西附近失事的法国航空447号飞机大概就沉入水中这一深度,但数据表明黑匣子依然有可能出现。)选项A(黑匣子依然很有可能被恢复)符合题意。选项B、C、D在原文中均未提及。因此选A。
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