题干

如图所示,在竖直平面内用细线悬挂一个小球,将小球拉至A点,由静止开始释放小球,不计空气阻力,小球可在A,C两点间来回摆动,以下说法正确的是(   )

A:小球在最低点B时动能最大,若在此点绳子突然断开,小球将做匀速直线运动

B:小球由A点运动到B点的过程中,机械能守恒

C:小球在C点时受力平衡

D:小球由A运动到B的过程中只有重力对小球做功,细线的拉力对小球不做功

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B,D

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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.