某单活塞杆液压缸的活塞直径D为80mm，活塞杆直径d=50mm，现用流量Q为30L/min，压力p为3Mpa的液压泵供油驱动，试求：1）液压缸能推动的最大负载2）差动工作时，液压的速度提示：需将所有单位转换成国际单位在计算：如L/min转换为m³/s；mm转换为m

A. 对
B. 错

A. The nearest hotel.
B. The nearest park.
C. The nearest shopping center.
D. The hotel next to the park.

A. By taxi.
By bus.
C. On foot.
D. By bike.

A. 50 minutes.
B. 5minutes.
C. 15minutes.
D. 25minutes.