房地产主要有（）的特性。
A.收入的连续性与周期性长
B.产业关联性高与依附性大
C.变现困难与保值增值
D.价值量大与不受限制
参考答案：C
在△ABC中，“sin2A=sin2B”是“A=B”的（ ）
A．充分不必要条件
B．必要不充分条件
C．充分必要条件
D．既不充分也不必要条件
Fire protection regulations for towing vessels require that drills be conducted on board the vessel as if there were an actual emergency. Drills include all of the following，EXCEPT（）.
A.testing all alarm and detection systems
B.breaking out and using the vessel's emergency equipment
C.participation by selected crew members
D.one person putting on protective clothing，if the vessel is so equipped
