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An observer 1.5 m tall is 20.5 m away from a tower 22 m high. The angle of elevation of the top of the tower from the eye of the observer is
A45 degrees
B30 degrees
C60 degrees
D75 degrees
Answer & Solution
Correct answer: A. 45 degrees
1. Effective vertical height = 22 minus 1.5 = 20.5 m.
2. tan(theta) = 20.5 / 20.5 = 1.
3. theta = arctan(1) = 45 degrees.
_Source: NCERT Class 10 Mathematics, Ch 9 "Some Applications of Trigonometry", §9.2_
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