空重车调整阀的支点调整部由()、从动辊、滚筒、旋转移动棒、旋转位置调整螺丝等构成。
鼠疫的传播途径有() ["飞沫传播","血液传播","鼠蚤传播","消化道传播","皮肤传播"]
当水位高至Ⅲ值时,保护系统动作()。 ["A、发出预告信号;","B、开启事故放水门;","C、发出停炉信号。"]
下列哪一种枝的顶端优势强() ["A、斜生枝","B、水平枝","C、直立枝"]
下列属于国际检疫传染病的传染病是() ["流脑","鼠疫","伤寒","霍乱","炭疽"]
缩写BECU的含义是:().