题干

某学生做完实验后,采用下列方法清洗所用仪器下列对以上操作的判断.正确的是(  )

①用浓氨水清洗做过银镜反应后的试管

②用酒精清洗做过碘升华的烧杯

③用浓盐酸清洗做过高锰酸钾分解实验的试管

④用盐酸清洗长期存放三氯化铁溶液的试剂瓶

⑤用氢氧化钠溶液清洗盛过苯酚的试管

⑥用热氢氧化钠的浓溶液清洗沾有硫磺的试管.

A:除①外都对   

B:除⑥外都对

C:④⑤不对

D:全都正确

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A

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    It's well-known by all the people to greet friends with a smile and a wave.____ However, what happens if your face and body send mixed messages? Would someone tend to believe the look on your face or the way you behave?

    Recently, scientists have dealt with these questions. They found that when a person is staring at your face, he might not believe what he sees if your body doesn't match the feeling that your face shows.____ Previous study had showed that the tone of a person's voice can be more important than the words spoken. For example, most people are more likely not to believe a person who says in a flat voice, “I'm so excited.”

    When talking about emotions conveyed by facial expressions and body language, most scientists suspected that the face was more important. To test if this was true, psychologists from the Netherlands and Boston showed people a number of pictures of isolated faces and isolated bodies that showed anger or fear.____

    An angry face had low eyebrows and tight lips. A frightened face had high eyebrow and a slightly open mouth.____A scared body had arms forward and shoulders square, as if ready to fight back.

These results told the researchers that mixed messages can confuse people. Even when people pay attention to the face, body language surely influences the emotion they read.

    ____And if you want to be understood it helps to avoid sending mixed messages.

A. Studying such mixed messages is nothing new for scientists.

B. So, your body language is important for telling people your feelings.

C. Scientists feel new to study the mixed message that puzzles people.

D. An angry body had arms back and shoulders at an angle, as if ready to fight.

E. Body language can sometimes be misunderstood in different culture backgrounds.

F. They also showed pictures where angry or scared faces were paired with angry or scared bodies.

G. When doing this, your face and body work together to show your friends that you are happy to see them.