阅读下面短文并回答问题，然后将答案写到答题卡相应的位置上（请注意问题后的词数要求）。Apple has entered the textbook market. The tech

阅读下面短文并回答问题，然后将答案写到答题卡相应的位置上（请注意问题后的词数要求）。
Apple has entered the textbook market. The tech giant introduced iBooks textbooks a couple of weeks ago when it announced its iBooks 2 platform. They are digital books in a variety of subjects from astronomy to zoology taking in science, maths, history and geography. Apple developed its iPad-based textbooks in connection with major textbook publishers. The company offers a collection of textbooks for high school students.
It sounds like good news for pupils and students. Think of it. No more full of textbooks. Every textbook you require can be stored on your iPad. Of course there’s a catch. You need to own an iPad and as you know, it is not cheap. You also need to buy digital textbooks, mostly priced each at $14.99 (94.74 yuan) or less. Textbook publishing was worth $8.7 billion in the US alone last year. Will digital books take over completely in education? Is learning going to evolve into something we do on an electronic tablet computer? That remains to be seen.
【小题1】What’ s the main idea of the text? (no more than 10 words)

【小题2】Fill in the blank in Paragraph 2 with proper words. (no more than 3 words)

【小题3】 What does the underlined word “it” in Paragraph 1 refer to? (no more than 3 words)

【小题4】What are the advantages of iBooks textbooks? (no more than 15 words)

【小题5】Do you think digital books will replace traditional books in the future,why or why not? (no more than 25 words)（略）

(答案→)（略） 解析：【小题1】 Apple has entered the textbook market. 根据第一句话可知 【小题2】 carrying heavy backpacks/ schoolbags 根据上下文可知，这里讲的是减轻学生的书包的负担【小题3】 The tech giant/ Apple 根据The tech giant introduced iBooks textbooks a couple of weeks ago可知【小题4】 Every textbook/ All textbooks can be stored on iBooks textbooks, which are easy to carry and light.根据第二段Every textbook you require can be stored on your iPad可知。【小题5】. It takes time for digital books to replace traditional books because it’s not realistic for every student to own an ipad.

就是这个解释

回答的不错

D解析分析：因两电阻串联，则由串联电路的电流规律可知两导体中的电流关系；由于电阻的大小与导体的材料、长度、横截面积有关，故由题意可知两部分电阻的大小关系，再由欧姆定律可求得两部分导体两端的电压关系．解答：因两电阻串联，所以通过两部分导体的电流相等即IAB=IBC；∵导体AB和BC的材料相同，长度相同，但是横截面积不同，且SAB＜SBC，∴AB段的导体电阻大于BC段的电阻，根据欧姆定律可知，AB段的电压要大于BC段的电压即UAB＞UBC．故选D．点评：本题考查串联电路的电流规律及影响电阻大小的因素，同时也检测了同学们对于欧姆定律的应用情况，熟记电阻大小与导体的长度成正比与导体的横截面积成反比的关系、并能利用欧姆定律做定性的分析是解决该题的关键．