问题
单项选择题
压井作业中,如果泵速从30冲/分增加到40冲/分,而立压保持30冲/分时的立压,对井底压力有何影响?()
A、减少.
B、不变
C、增加.
答案
参考答案:A
压井作业中,如果泵速从30冲/分增加到40冲/分,而立压保持30冲/分时的立压,对井底压力有何影响?()
A、减少.
B、不变
C、增加.
参考答案:A
选择合适的疑问词,把序号填在横线上。 | |
2. _____________ are you? I'm eleven. 3. _____________ is it? It's seven o'clock. 4. _____________ balls can you see? I can see five. 5. _____________ is the music room? It's near the library. |