Subject: Can you help?            

From: Rose

Dear Knowledgeable,

    I have a good friend, Ann. She is very clever and can speak English really well. A very important English speech contest for our whole city will be held next month. Our classmates all think Ann is the best person to represent the class in the school contest and make sure she will win. But the problem is that she's very shy and that she's terrified of speaking in front of other people.

    She can't tell others about it, because she doesn't want to let her friends down. I can't think of any good advice to give her, but you always come up with good solutions to people's problems. Can you give us some good advice？Do you think we can tell the truth to the rest of the students?

Yours,

Rose

某校有老师200名，男生1200名，女生1000名，现用分层抽样的方法从所有师生中抽取一个容量为240的样本，则从男生中抽取的人数为____ 

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