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An aeroplane flying horizontally 1 km...

An aeroplane flying horizontally 1 km above the ground is observed at an elevation of `60o` . After 10 seconds, its elevation is observed to be `30o` . Find the speed of the aeroplane in km/hr.

A

240

B

`240sqrt3`

C

`60sqrt3`

D

None of these

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A, B, C, D
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ARIHANT MATHS-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise (Questions Asked In Previous 13 Years Exam)
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