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Consider a triangular plot ABC with side...

Consider a triangular plot ABC with sides AB = 7 m, BC = 5 m and CA = 6 m. A vertical lamp-post at the mid-point D of AC subtends an angle `30^(@)` at B. The height (in m) of the lamp-post is

A

`(2)/(3)sqrt(21)`

B

`2sqrt(21)`

C

`7sqrt(3)`

D

`(3)/(2)sqrt(21)`

Text Solution

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The correct Answer is:
A
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