假如你叫刘明，是美国中学生艾丽斯的朋友，你收到了她的电子邮件，请给她回复，回答她的问题，提出你的建议。并就此事谈谈你的看法。
内容应包括：
你是否遇到过这样的问题？
该借给她钱还是不借给她钱？
若她忘记归还该怎么办？
注意：恰当运用条件状语从句，句子结构要完整，80词左右。
Dear Liu Ming,
Hi! I’m so sad. Angela is a close friend of mine. This morning she wanted to borrow some money from me. If I lend her the money, I’m afraid she won’t pay me back. I don’t know what to do. Do you have the same problem? I need your help. I’m looking forward to hearing from you soon.
Yours,
Alice
Dear Alice,
I’m glad to hear from you .
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I hope what I said can help you.
Yours,
Liu Ming
，所以外接圆半径
。由三角形面积公式
可知，
。又
,所以
,即
。所以选D。