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如图,为测得河对岸塔AB的高,先在河岸上选一点C,使在C塔底B的正东方向上,测得...
如图,为测得河对岸塔AB的高,先在河岸上选一点C,使在C塔底B的正东方向上,测得点A的仰角为60°,再由点C沿北偏东15°方向走10米到位置D,测得∠BDC=45°,则塔高AB的高度为( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100940292596405/SYS201311031009402925964009_ST/images0.png)
A.10
B.10
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100940292596405/SYS201311031009402925964009_ST/0.png)
C.10
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100940292596405/SYS201311031009402925964009_ST/1.png)
D.10
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100940292596405/SYS201311031009402925964009_ST/2.png)
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