Answer:
(B) 42°
Explanation:
The triangle LMN is inscribed in a semi-circle so therefore, if LM is the diameter, m∠LMN is 90°. Then, if one angle in ΔLMN is 90° and another is 48°, the third angle (∠NLM) will be 42° (The sum of the angles in a triangle is 180°).
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