到三角形各顶点的距离相等的点是三角形（ ） A．三边的垂直平分线的交点 B．三条高的

—How do you do?           

—         ?[ ]

A. How are you?            

B. How old are you?          

C. How do you do?

废钢的检验项目有斗重、（）、（）、单重、（）。

房地产市场需求指标不包括( )。

A．国内生产总值
B．空置率
C．人口数量
D．房屋空间使用数量

If you saw flames aboard a vessel but could see the vessel was not on fire，you would know that the（）.

A.crew was trying to get warm

B.vessel required immediate assistance

C.vessel was attempting to attract the attention of a pilot boat

D.vessel was being illuminated for identification by aircraft

对游客个别要求的处理原则是什么