使用竹梯作业时，梯子放置与地面夹角以50°左右为宜。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='27282' and id < 2260600 and id<>'2260600' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='27282' and id > 2260600 and id<>'2260600' order by id asc limit 5