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某实验小组对酸奶中乳酸菌的数量进行了测定,取6支灭菌的试管,分别加入9mL灭菌的生理盐水,标号A1、A2、A3、A4、A5、A6,吸取1mL酸奶样液中加入试管A1中,然后另取一支吸管从A2中吸取1mL溶液,加入A2中,依此类推,最后从试管A6中取0.1mL样液进行涂布计数,涂布三个平板,其菌落数分别为251、265、276个.请回答下列问题:
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同类题3

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    Taking good notes is a time-saving skill that will help you to become a better student in several ways ____.Second, your notes are excellent materials to refer to when you are studying for a test. Third, note-taking offers variety to your study time and helps you to hold your interest.

    You will want to take notes during classroom discussions and while reading a textbook or doing research for a report. ____ Whenever or however you take notes, keep in mind that note-taking is a selective process. ____

    The following methods may work best for you.

●Read the text quickly to find the main facts and ideas in it.

●Carefully read the text and watch for words that can show main points and

supporting facts.

● Write your notes in your own words.

____

● Note any questions or ideas you may have about what was said or written.

    As you take notes, you may want to use your own shorthand(速记). When you do, be sure that you understand your symbols(符号) and that you use them all the time. ____

A.Use words, not complete sentences.

B.There are three practical note-taking methods.

C.You must write your notes on separate paper.

D.Otherwise, you may not be able to read your notes late

E. you will also want to develop your own method for taking notes.

F. That means you must first decide what is important enough to include in your notes.

G. First, the simple act of writing something down makes it easier for you to understand and remember it.