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下图为我国某地局部降水（雪）分布图。读图，完成下列各题。

下列对甲、乙两地天气的叙述，正确的有（）

①甲地中雨，乙地中雪

②甲地小雪，乙地小雨

③甲、乙两地风向均为偏北风，乙地风力较强

④甲、乙两地风向均为偏南风，甲地风力较强

A.①③

B.①④

C.②③

D.②④

答案

参考答案：A

解析：

根据图示，甲乙两地降雨（雪）强度为中等，甲地在雨雪分界线以南，为中雨，乙地在雨雪分界线以北，为中雪。图中两条等压线偏北的一条值较高，所以甲乙两地都是偏北风；乙地比甲地的等压线密集，风力比甲地大。

考点：等值线图

解答题
先化简，再求当x=
9
13
时的值．（x-2）（x2-2x+4）-x（x+3）（x-3）+（2x-1）2．
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