第19题:[多选题]消防应急照明和疏散指示系统说法正确的是()。 A.其外壳应选用不燃或阻燃材料 B.消防应急照明和疏散指示系统的外壳防护等级应在产品标志或使用说明书中注明 C. 室外使用的消防应急照明和疏散指示系统应具有防尘功能、防水功能和耐磨功能 D.地面安装使用的消防应急照明和疏散指示系统产品应具有防水功能和耐磨功能 参考答案:ABD
第20题: [单项选择]The laser represents a true marriage between science and technology, the men who devised it were ______ engineers and physicists. A. spontaneously B. simultaneously C. instantaneously D. homogeneously 参考答案:B
第29题: [单项选择]The underlined phrase "dry run" in the third paragraph means______. A. to run to work B. to test the route in advance in person C. not to make your feet wet on the way work D. to walk as quickly as possible 参考答案:B 答案解析:[解析] 语义理解题。利用上文的信息punctuality impresses and nothing annoys bosses or new colleagues more than late s
第31题: [单项选择]An occluded front is usually caused by a（）. A. cold front becoming stationary B. warm front becoming stationary C. cold front overtaking a warm front D. warm front dissipating 参考答案:C
第32题: [单项选择]冠心病中通常所说的三支病变是累及哪三支血管（） A. 右冠状动脉、回旋支、前降支 B. 锐缘支、后降支、右室前支 C. 回旋支、前降支、顿缘支 D. 对角支、前降支、锐缘支 E. 以上都不是 参考答案:A
