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The angle B is:

(A) 120°

(B) 60°

(C) 90°

(D) 45°

Answer :

Given, in \(\triangle\) ABC, AB = \(6 \sqrt {3}\) cm, AC = 12 cm and BC = 6 cm.

We can observe that,

\(AB^2 = 108\)

\(AC^2 = 144\)

And,\( BC^2 = 36\)

\(AB^2 + BC^2 = AC^2\)

The given triangle, \(\triangle\) ABC, is satisfying Pythagoras theorem.

Therefore, the triangle is a right triangle, right-angled at B.

\(\angle\) B = 90°

Hence, the correct answer is (C).

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