换装或搬运钢轨、轨枕、辙叉等笨重轨料时，应怎样做？
参考答案：
应有专人指挥，尽量在平整的地面行走；必须在坑洼不平或在线路上行走时，应注意踏稳踩牢。
WebSQL is a SQL-like （71） language for extracting information from the web. Its capabilities for performing navigation of web （72） make it a useful tool for automating several web-related tasks that require the systematic processing of either all the links in a（73） , all the pages that can be reached from a given URL through （74） that match a pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common （75） Interface.
A．paths
B．chips
C．tools
D．directories
某市自来水收费标准如下：每户每月用水4吨以下，每吨1.80元。当超过4吨时，超过部分每吨3.00元。某月甲、乙两户共交水费26.40元，用水量之比为5:3，问：乙应交多少水费( )
A．8.70元 B．9.90元 C．10.20元 D．16.50元
