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问题 选择题

如图所示，长方体金属块边长之比a:b:c=3:1:2，将A与B接入电压为U的电路中时，电流为I；若将C与D接入电压为U的电路中，则电流为（设金属块的电阻率不变）   

A．I　　

B．2I

C．

D．

答案

答案：C

题目分析：由电阻定律得，同理，则，根据欧姆定律，电压相同时，电流与电阻成反比，则将C与D接入电压为U的电路中，电流为。

故选C

点评：根据电阻定律公式确定两次电阻值之比，然后根据欧姆定律确定电流间的关系。

完形填空

信息匹配（共5小题；每小题2分，满分10分）

阅读下列应用文及相关信息，并按照要求匹配信息。请在答题卡上将对应题号的相应选项字母涂黑。首先请阅读下列儿童读物的封面及基本信息：

  

下面是这些书的简要内容。请把相关的内容与它们的书名匹配起来。

小题1:This picture book explores the life of a tree that has deep roots，long arms，and many children. She provides shelter for many animals and bears fruit. The author uses colorful, simple，yet detailed watercolor illustrations to convey her words. The charming pictures show the many aspects in the life of a tree down to the caterpillars that eat the leaves. It is good for pre-school children.

小题2:This charming picture book highlights the life of a garden，from planting seeds to harvesting. With the narrator as guide，the reader is led through a variety of free verse and occasionally rhymed poems that fill in the story of a garden and its inhabitants. The pictures. delightful watercolors in bright pastels，add to the whimsical feel of the poems. Young readers will certainly enjoy this fun and fanciful text.

小题3:This is a story from 1956 which introduces a little boy who likes to go fishing with a tree limb， a woman，and a pin. Although he never catches anything，on this particular day he finally does hook three big ones，but the little one gets away. The boy pulls them home in his wagon and his mother cooks them for supper. The swinging rhythms of the text and the good humor evident in the illustrations remain fun for the youngest readers.

小题4:This useful，attractive，oversize volume uses its height well，employing a tree metaphor to show the earth’s various kinds of life and how all living things. from bacteria to the largest mammals，are related. Each spread covers one branch of the animal kingdom. To make the enormity of species understandable. Strauss equates individual species（e. g. ，1 0，000 bacteria）with one leaf on the tree.

小题5:This is a story about how a grandfather teaches his eager granddaughter to catch speckled trout from the stream in springtime. After a whole day on the lake，only Grandpa is lucky. The next morning the young fisherman hurries to the dock alone，and soon she hooks the catch of a lifetime. Young readers will appreciate this story that celebrates the special bond between the older and younger generation，while brilliant watercolor illustrations capture the beauty of the natural world
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选择题

下图是“世界能源消费构成变化图”。读图完成：

下列说法与上图所反映的能源消费构成变化一致的是

A．大约在19世纪80年代进入煤炭时代

B．从1890始，煤炭的比重不断下降

C．世界能源利用多样化时代结束于1950年

D．图中的五类能源均由太阳能转化而来
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