题干

小明同学从S+O2 SO2中获得以下信息(        )

①该反应反应物是硫和氧气;②反应发生条件是点燃;③反应前后元素种类和原子个数不变;④反应前后分子总数保持不变;⑤参加反应的硫和氧气的质量比为2:1。

A:①②④⑤

B:①②③

C:④⑤

D:①②③⑤

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答案(点此获取答案解析)

B

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    Everyone can benefit a lot from reading books. The following is about various benefits of reading books.

    ____ Whenever you read something, you learn information that you wouldn't have known. If you want to learn new words, reading books is a great way to enlarge your vocabulary.

    ____ Similar to solving puzzles, reading books allows your mind to practice its processing skills. Going without books for too long will turn your mind into mess.

    One of the primary benefits of reading books is its ability to develop your thinking skills.____ Wherever you are faced with a similar problem in real life, your mind is able to put its mystery solving skills to a test.

    The information in books can be referred to over and over again. For example, reading a cookbook allows you the chance to review the cooking steps whenever you need to.____Don't even think about writing the information down because you may lose the paper sooner or later.

    These are just some of the wonderful benefits of reading books.____ If you can't even go outside, you can download free e­books online and read them on your computer. That way, you can see how useful reading can be for yourself.

A. You can improve your memory by reading.

B. Reading keeps your mind in good condition.

C. Reading books can make you become confident.

D. Reading books provides you with new knowledge.

E. Reading mystery novels, for example, trains your mind.

F. Following the steps from a cooking video will be difficult.

G. Why don't you drop into a bookstore and pick a book up?