轻度有机磷中毒的临床表现是（）。
A.呼气有大蒜样臭味
B.出汗、无力
C.瞳孔缩小
D.肌纤维颤动
E.呼吸肌麻痹
参考答案：A, B, C
为什么向锅炉进水前先要进行除氧器加热？
10BaseT is an Ethernet LAN tem meaning a maximum transfer rate of 10 Mbps that uses baseband signaling and twisted pair cabling. A 10BaseT Ethernet LAN has a ______ topology.
A．star
B．ring
C．bus
D．none of the above
