—This book educating teenagers. Would y

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问题选择题

—This book educating teenagers. Would you like to buy it?

—Yes, I'll take it. [ ]

A. is aimed at

B. depends on

C. give out

D. sets up

答案

答案：A

阅读理解

阅读小天地。根据短文内容判断下列句子的正(√)误(×)。

It is Christmas Eve now. My sister and I are very busy. We are putting some colour lights and our

Christmas presents on the Christmas tree. There is also a big red star on top of the tree. My sister is putting

some Christmas cards on the shelf. There are cards for everyone in our family and there are some presents

for everyone, too.

( ) 1. It is Christmas day now.

( ) 2. My brother and I are very busy on that day.

( ) 3. There is also a big red star on top of the tree.

( ) 4. My sister is putting some Christmas cards on the tree.

( ) 5. There are cards and some presents for everyone.

填空题

小明利用标有“6V 6W”的灯泡L₁和标有额定电压为6V的L₂进行实验：

（1）分别对通过L₁和L₂中的电流和两端电压进行测量，绘制了电流随两端电压变化曲线图甲所示，A、B分别对应L₁和L₂,则L₂的额定功率为 _ W。

（2）现将两灯连入图乙所示电路。实验过程中，小明不慎把电路中的L₂的玻璃泡打碎了（碰巧灯丝没有断），此时他惊奇的发现：这个小灯泡几乎不发光，可另一个灯L₁反而更亮了。①你认为L₂变暗的原因是：_______________________________。

②此时电路消耗的总功率与原来相比将__。（选填“变大”、“变小”或 “不变”）

（3）小明用一只新的同样规格的L₂将打碎玻璃泡的灯更换后，要使其中一只灯泡正常发光，此时电源电压为 V。