离心泵的扬程和升扬高度相同，都是将液体送到高处的距离。
参考答案：错
---Has Jack finished painting the picture yet?
--- I’ve no idea. But he______ it the whole afternoon.
A．was painting
B．painted
C．had painted
D．have painted
车辆一级保养是以什么为中心（）
A、小修
B、调整
C、清洁
D、紧固、润滑
