若tan=3，则的值等于（    ）

汽车发动机在工作过程中需要冷却．图为汽车发动机的水冷系统工作原理示意图．在汽车发动机正常工作的过程中，图所示有关汽车发动机水冷系统中水流方向以及水泵叶轮转向的示意图中，正确的是（　　）

如图，若A是实数a在数轴上对应的点，则关于a，-a，1的大小关系表示正确的是（　　）

如果诸侯不履行自己的义务，或超越周王赋予他们的特权，周王可以废除给他们的封地和爵禄，甚至消灭他们。以上解读源于（  ）

      Mr Jones was a millionaire(百万富翁). One day he went to stay at a hotel in New York. He hoped to have the cheapest room to live in. Mr Jones asked, "What price(价格) is the room?". The boss (老板) told him. "And which floor is it on?" Again the boss told him. "Is that the cheapest room you have? I' m staying here by myself and only need a small room. "
     The boss said, "That room is the smallest and cheapest we have. But why do you choose a poor room like that? When your son stays here, he always stays at our dearest room. Yours is the cheapest. " "Yes," said Mr Jones, "his father is a very rich man, but mine isn' t.