Answer:
B.m∠QLP = 50
C. m∠NLO + m∠OLP = m∠NLP
D. m∠QLP + m∠PLO = m∠MLN + m∠NLO
Explanation:
∵ In the compass, the angle from the terminal side to clockwise direction is estimated by the above scale and the angle from the terminal side to anticlockwise direction is estimated by the below scale,
Thus, by the given compass,
m∠MLN = 60°,
m∠MLO = 90°,
m∠QLO = 90°,
m∠QLP = 50°
∠NLP can be divided into angles ∠NLO and m∠OLP,
⇒ m∠NLO + m∠OLP = m∠NLP
Now, ∠MLN and ∠NLO are linear pairs,
⇒ m∠MLN + m∠NLO = 180°,
Similarly,
∠QLP and ∠PLO are linear pairs,
⇒ m∠QLP + m∠PLO = 180°,
⇒ m∠MLN + m∠NLO = m∠QLP + m∠PLO
∠MLN and ∠NLO parts of angle ∠MLO,
⇒ m∠MLN + m∠NLO = m∠MLO,
⇒ m∠NLO = m∠MLO - m∠MLN
Similarly,
∠OLP and ∠QLP parts of angle ∠QLO
⇒ m∠OLP + m∠QLP = m∠QLO,
⇒ m∠OLP = m∠QLO - m∠QLP
But, m∠NLO ≠ m∠OLP
⇒ m∠QLO − m∠QLP ≠ m∠MLO − m∠MLN