From a point on the ground, 30 m away from the foot of tower, the angle of elevation of the top of the tower is 30°. The height of the tower is

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Let AB be the tower and C be the point on the ground, 30m away from B. Given that, BC = 30m, the angle of elevation, ACB = 30°. Join A, C and B,C. We get a right-angled triangle. We use trigonometric ratio tan taking AB as the height and BC as the base. In ∆ABC,



or,



So, the correct option is (B).

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