题目详情:

[单项选择]
Passage Five Many animals are used to help scientists find cures for diseases. One of the most common animals used is monkeys, or primates. There are groups of people who want to stop the research on animals. They are called animal rights activists. The scientists say their research could help save the lives of many men, women and children. They try to cure diseases like cancer and AIDS. The animal rights activists say the animals suffer. They take baby monkeys away from their mothers, and sometimes holes are drilled in their heads. The activists have tried to stop the research for the past 10 years. They let animals go free or damage the labs. The University of California at Davis has 3,800 rhesus macaque monkeys. It is one of the largest primate research labs. The activists sent letters to researchers at Davis and about eighty other researchers around the country, whose names were on the web pages. The warning letters had razor blades hidden so that a person could slice
A. increasing
B. decreasing
C. ending
D. staying about the same

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[单选题](1.0分)检测灌注桩桩缺陷及其位置,判定桩身完整性类别是( )。
A.钻芯法
B.单桩竖向抗压静载试验
C.单桩水平静载试验
D.声波透射法

[判断题]开关中装有的RC阻容吸收装置是过电压保护装置。 ( )
A.正确
B.错误

[单项选择]Navigation computers, now sold by most car-makers, cost $ 2,000 and up. No surprise, then, that they are most often found in luxury cars, like Lexus, BMW and Audi. But it is a developing technology — meaning prices should eventually drop — and the market does seem to be growing. Even at current prices, a navigation computer is impressive. It can guide you from point to point in most major cities with precise turn-by-turn directions — spoken by a clear human-sounding voice, and written on a screen in front of the driver. The computer works with an antenna (天线) that takes signals from no fewer than three of the 24 global positioning system (GPS) satellites. By measuring the time required for a signal to travel between the satellites and the antenna, the car’’s location can be pinned down within 100 meters. The satellite signals, along with inputs on speed from a wheel-speed sensor and direction from a meter, determine the car’’s position even as it moves. This information is combined with a map database. Streets,　landmarks and points of interest are included. Most systems are basically identical. The differences come in hardware — the way the computer accepts the driver’’s request for directions and the way it presents the driving instructions. On most systems, a driver enters a desired address, motorway junction or point of interest via a touch screen or disc. But the Lexus screen goes a step further: you can point to any spot on the map screen and get directions to it. BMW’’s system offers a set of cross hairs (瞄准器上的十字纹) that can be moved across the map (you have several choices of map scale) to pick a point you’’d like to get to. Audi’’s screen can be switched to TV reception. Even the voices that recite the directions can differ, with better systems like BMW’’s and Lexus’’s having a wider vocabulary. The instructions are available in French, German, Spanish, Dutch and Italian, as well as English. The driver can also choose parameters for determining the route: fastest, shortest or no freeways (高速公路) , for example. The navigation computer functions ____________.
A. by means of a direction finder and a speed detector
B. basically on satellite signals and a map database
C. mainly through the reception of turn-by-turn directions
D. by using a screen to display satellite signals