Answer: Choice B
∠LMN is an obtuse angle.
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Step-by-step explanation
Let's go through the answer choices to see which are true, and which are false.
- A. This is false. It is stated that "LMN is greater than 90 degrees", so this angle is obtuse. Acute angles are less than 90 degrees.
- B. This is true. See choice A above.
- C. This is false. We're told that "angle MNO is less than 90 degrees". That makes the angle acute.
- D. This is false. See choice C above. Right angles are 90 degrees exactly. Often a small square marker is used to denote a 90 degree angle.