离心泵开车前,开泵进口阀向泵内灌满液体,确认泵内及进口管道内气体已排尽。
参考答案:对
根据单词首字母提示和句意完成下列句子。
1. I got up late yesterday because I o_____.
2. He gave me a r_____when he saw me walking alone.
3. She didn't s _____up at his party.
4. Lucy is so e _____now that she isn't going to do anything.
5. Mr. Wang a _____that we we'll have a picnic tomorrow.
6. What words can you use to d _____surfing?
7. Only Tony didn't f_____from that house while the earthquake took place.
8. His sister is going to m _____a businessman next week.
9. I phoned him many times but he didn't r_____even once.
10. The truth will be r _____someday.
数据库系统发生故障时,可以基于日志进行恢复。下面列出的条目中, ( )是日志记录的内容。 Ⅰ.事务开始信息 Ⅱ.更新信息 Ⅲ.提交信息 Ⅳ.事务中止信息
A.Ⅰ、Ⅱ和Ⅳ B.Ⅰ、Ⅲ和ⅣC.Ⅱ、Ⅲ和Ⅳ D.都是