污泥预处理的目的( )。
A．改善污泥脱水性能
B．使污泥脱水速度加快
C．降低污泥比阻
D．以上全对
参考答案：D
—I can't go with you today. There will be a test tomorrow.
— Maybe next time. [ ]
A. It doesn't matter
B. My pleasure
C. I don't think so
D. Sorry to hear that
