题型:名词解释 Mr. Green drove slowly on the way home until he reached the highway, ____ the speed limit was 60 miles per hour. [ ]A. because B. which C. where D. that 查看答案
题型:名词解释 下列关于超声波物位计安装说法,正确的是()。A.液位计安装时,探头和容器壁不可靠得太近,以防止回波产生干扰B.液位计的探头必须垂直安装,以保证收到最强的回波C.安装位置附近不应有较大的振动D.以上都是 查看答案