单项选择题
1、下列物质存在同分异构体的是（　　）



2、 抛物线y2=-4x的准线方程为    (     )
A．x=-1   
B．x=1
C．y=1 
D．Y=-l


3、
A．y²=-4x
B．y²=-8x
C．y²=-9x
D．y²=-18x


4、阅读下列短文，回答题。
      Not many years ago, a wealthy and rather strange old man named Johnson lived alone in village in the south of England． He had made a lot of money in trading with foreign countries． When he was seventy-five ,he gave $1200 to the village school to buy land and equipment for a children's playground．
     As a result of his kindness, many people came to visit him． Among them was a newspaperman． During their talk, Johnson remarked that he was seventy-five and expected to live to be a hundred． The newspaperman asked him how he managed to be healthy at seventy-five． Johnson had a sense of humour (幽默)． He liked whisky (威士忌酒) and drank some each day． "I have an injection(注射) in my neck each evening," he told the newspaperman, thinking of his evening glass of whisky．The newspaperman did not understand what Johnson meant． In his newspaper he reported that Johnson was seventy-five and had a daily injection in his neck． Within a week Johnson received thou-sands of letters from all over Britain, asking him for the secret of his daily injection．
The gift of money to the school suggests that Johnson
A．had no children
B．was a strange man
C．was very fond of children
D．wanted people to know how rich he was


5、
A．{x|-1B．{x| 0C．{x| 0D．{x|-1
6、 函数f(x)=log₂(x-1)(x>1)的反函数为
A．y=2x+1(x∈R)
B．y=2x-1(x∈R)
C．y=2x+1(x>1)
D．y=2x-1(x>1)


7、设全集U={1，2，3，4，5，6，7，8，9}，集合A={1，3，5，7}，B={2，4，5，8，9}，则A∩[_UB=
A．{2，4，8，9}
B．{5}
C．{1，3，5：6，7}
D．{1，3，7}


8、 If only she __________ her necklace that night.
A．didn't lose
B．wouldn't lose
C．hadn't lost
D．hasn't lost


填空题
9、
实验步骤及现象如下：
(1)取少许此溶液进行焰色反应，火焰显黄色；透过蓝色钴玻璃观察，火焰不显浅紫色。
(2)取少量此溶液加入稀盐酸中，反应生成无色无味气体。
(3)取少量此溶液加入氯化钙溶液中，没有白色沉淀生成。
依据以上的实验现象，可推知这瓶溶液中肯定含有的离子是__________，不含有的离子是__________。


简答题
10、(12分)如图，一闭合电路中，电源电动势为E=12 V、内阻为r=1Ω，电路中的电阻R₁=1.5Ω，R₂=R₃=3Ω，R₄=6Ω。求
(1)通过电阻R₁的电流；
(2)B、C两点间的电势差U_BC。

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