Unless we spend money to spot and
prevent asteroids (小行星) now, one might crash into Earth and destroy
life as we know it, say some scientists. Asteroids are bigger versions of the meteoroids (流星) that race across the night sky. Most orbit the sun far from Earth and don’t threaten us. But there are also thousands whose orbits put them on a collision course with Earth. Buy $ 40 million worth of new telescopes right now. Then spend $10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a w A. Optimistic. B. Critical. C. Objective. D. Arbitrary. [单选题]单置调车信号机按钮做变通按钮使用时,( )吸起。[321020201]
A.AJ↑2AJ↑ B.1AJ↑AJ↑ C.1AJ↑2AJ↑AJ↑ D.1AJ↑2AJ↑ [判断题]不需要高压线路、设备停电或做安全措施的配电运维一体工作,可使用其他书面记录或按口头、电话命令执行。
A.正确 B.错误 [单选题]加油车配备灭火瓶的种类是﹛.XZ﹜。
A.干粉灭火器 B.二氧化碳灭火器 C.泡沫灭火器 D.清水灭火器 [判断题]一切单位和个人都有保护环境的义务,并有权对污染和破坏环境的单位和个人进行检举和控告。
[单项选择]肺胀的病理因素,主要责之于()
A. 肺肾两虚,气失摄纳 B. 心肾阳虚,水气凌心 C. 痰浊水饮与血瘀互为影响,兼见同病 D. 痰气交阻,伤及肺脾肾,本虚标实 E. 阴盛阳微,本虚标实 [判断题]根据《煤矿重大安全隐患认定办法(试行)》之规定:生产经营单位将煤矿(矿井)承包或者出租给不具备安全生产条件或者相应资质的单位或者个人的,不属于煤矿重大安全生产隐患。
[单选题]消防水池应设置取水口(井),且吸水高度不应大于()m。
A.10 B.8 C.7 D.6 [单选题]施工现场架空线路的同一横担上,LI、L2、L3、N、PE五条线的排列次序是面向负荷侧 从左起依次为()。
A.LI、 L2、 L3、 N、 PE B.LI、 N、 L2、 L3、 PE C.LI、L2、N、L3、PE D.PE、N、LI、L2、L3 [判断题]遇便携式列尾机车台和CIR均无法查询风压时,按《行规》列尾装置故障规定进行处理。
A.正确 B.错误 [填空题]
Both of them were presidents during the years of [单选题]水中含氟量以多少为宜,该浓度既能有效防龋,又不致发生氟牙症
A.1m9/L B.0.5m9/L C.0.5~1.0m9/L D.1.Sm9/L E.2.0m9/L 我来回答: 提交
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