(2008•芜湖)在我市迎接奥运圣火的活动中,某校教学楼上悬挂着宣传条幅DC,小丽同学在点A处,测得条幅顶端D的仰角为30°,再向条幅方向前进10米后,又在点B处测得条幅顶端D的仰角为45°,已知测点A、B和C离地面高度都为1.44米,求条幅顶端D点距离地面的高度.(计算结果精确到0.1米,参考数据:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230821942422330/SYS201310212308219424223009_ST/0.png)
≈1.414,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230821942422330/SYS201310212308219424223009_ST/1.png)
≈1.732.)
考点分析:
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