立式除油罐中污水停留时间要在()之间。
A.2~5h
B.3~4h
C.1~3h
D.12~10h
参考答案:B
—Don't _____, my children, keep working on and you will be successful.
—Thank you, Mr. Wang. We'll try our best. [ ]
A. put up
B. pick up
C. grow up
D. give up
如果某商品的价格从3美圆降低到2美圆,需求量从9单位增加到11单位,则该商品卖者的的总收益将()
A、增加
B、减少
C、不变
D、无法确定