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举一反三
【单选题】S模式航管雷达进行的三大改进是：（）
A.
单脉冲处理、选择性询问、数据通信
B.
脉冲处理、可用性、话音通信
C.
脉冲处理、选择性询问、可用性
D.
脉冲处理、话音通信、数据通信
【单选题】For the (26) month, mysterious falls of large chunks of ice (冰雹) (27) rained down on Spain and Italy. Juana Sanchez, a 70-year-old woman in Almeria, southern Spain, was knocked (28) when she was struc...
A.
Although eyewitnesses to the phenomenon report that they did not see anything in the sky that could account (44) the ice, scientists had to come up with a rationalization. Professor Jesus Martinez Frias, the geologist investigating the ice falls in Spain, told BBC News that the ice pieces had probably been (45) through sudden temperature drops in the stratosphere. This was the most likely explanation, he said, for the "very unusual" phenomenon.