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如图,测量河对岸的塔高AB时可以选与塔底B在同一水平面内的两个测点C与D,测得∠...
如图,测量河对岸的塔高AB时可以选与塔底B在同一水平面内的两个测点C与D,测得∠BCD=15°,∠BDC=30°,CD=30,并在点C测得塔顶A的仰角为60°,则塔高AB=( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101128007480280/SYS201311031011280074802002_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101128007480280/SYS201311031011280074802002_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101128007480280/SYS201311031011280074802002_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101128007480280/SYS201311031011280074802002_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101128007480280/SYS201311031011280074802002_ST/3.png)
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