一束与镜面成45°角的水平光线射在平面镜上，如图所示．请在图中画出反射光线并标明反射角的大小

．

修改：在错的词下画一横线，并在该词下面写出修改后的词。

注意：1 每处错误及其修改均仅限一词；

2只允许修改10处，多者(从第11处起)不计分。

DearTom，

Howis everything going? I have favor to ask.Next week，I was going to a reception at the City Hall.As is expected，I'll meet some high school student and their teachers invitingfrom America.

Theonly problem is that because I'm not very good at small talks with people Idon't know.So I am worried that I will make a fool of myself but make othersembarrassing.I wonder if you would be kindly enough to give me some tips inwhat I can talk about with people from America.Are there any questions that youshould not ask?

Lookingforward to your early reply.

Yours

Li Hua

（2015•枣庄）如图，平面上直线a，b分别经过线段OK两端点（数据如图），则a，b相交所成的锐角是____ .

$\frac{5}{12}\times \frac{6}{25}=$ ____     $\frac{9}{10}\times \frac{5}{18}=$ ____