题干

小红设计了如图甲所示的电路来测量一个未知电阻的阻值,其中Rx为待测电阻,R1为电阻箱,S为单刀双掷开关,R为定值电阻.实验主要步骤有:

A.把开关S接b点,调节电阻箱,使电流表的示数为I;

B.读出电阻箱的示数R1;

C.把开关S接a点,读出电流表的示数为I;

D.根据电路图,连接实物,将电阻箱的阻值调至最大.

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    Most people say “yes” much more readily than “no”.

    A friend is moving house this weekend and would like some help, and you agree. But, what you really wanted was a couple of quiet days relaxing at home. Or a roommate spends the entire weekends playing video games and wants to borrow your homework for “reference”. But, you've just finished it after taking a whole day to work hard.

    Many people say “yes” to those kinds of requests. They tend not to consider their own interests and feelings, and are often angry with themselves afterwards.

    Saying “no” requires courage and considerable practice, in fact, according to psychologists.

    “Everyone wants to be liked,” says Gabriel Steinki, a German psychologist. “Saying ‘no' risk losing the affection of the person asking the favor or even a job.”

    The result is that many people say “yes” just for keeping the peace. But experts say this is regrettable. Anyone should have the right to say “no”.

    In fact, rejecting a request can even help to strengthen a relationship because it expresses a true feeling.

    But, for people used to agreeing to every request, changing can be a long and uncomfortable learning process.

    Most people believe that “If I say ‘no', I'll lose the affection of the person. But the affection is important to me.” This way of thinking can be replaced by this “If he only likes me because I always do what suits him, then the price of his affection is too high in the long term.”

    Steinki says the key is talking to the other person to find a mutual(相互的) solution. “One needs to present the situation from one's own point of view, and to suggest how the situation can be dealt with to the advantage of both parties. The other person must have the feeling that his interests are being considered.”

    When the refusal is not accepted, Steinki advises giving the reasons calmly again until the person gets the message.