某人用焦距为10cm凸透镜看报纸上的字。则凸透镜与报纸间的距离应

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问题选择题

某人用焦距为10cm凸透镜看报纸上的字。则凸透镜与报纸间的距离应[ ]

A．小于10cm

B．大于10cm

C．大于20cm

D．在10cm和20cm之间

答案

答案：A

问答题

试述病理性黄疸的常见原因。

填空题

阅读下面的对话，根据上下文蒋空缺的内容补充完整，完成对话。每空不限填一个单词。

A :Hello, Mrs White. Come in and sit down.

B :Hello, doctor.

A : 小题1:

B :I've got a headache.

A : 小题2: you often have a headache ?

B :No, never. I've never had a headache before.

A : 小题3: have you been like this ?

B :About two or three hours ago.

A :Let me take your temperature. Oh, it's high fever. You must catch a bad cold.

B : 小题4: give me some medicine ? It's very painful.

A : Yes. I'll give you some pills, take one three times a day. You will 小题5: soon.

B :Thank you very much.

A :That's all right.