龙荟丸可用于治疗
A．脾虚性便秘
B．老年体虚便秘
C．肝胆火旺，大便秘结，小便干涩
D．实热便秘
E．脾肾两虚性便秘
参考答案：C
下列物质中不能用金属与稀硫酸直接反应制得的是[ ]
A.Fe2(SO4)3
B.MgSO4
C.Al2(SO4)3
D.ZnSO4
If your vessel is dragging her anchor in a p wind，you should（）.
A.shorten the scope of anchor cable
B.increase the scope of anchor cable
C.put over the sea anchor
D.put over a stern anchor
