Answer:
C. 38°
D. 30°
Explanation:
The relevant relation in both cases is the inscribed angle measures half the measure of the arc it intercepts.
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C. Angle TSQ intercepts arc TQ, so the measure of arc TQ is 2(86.5°) = 173°. The measure of arc TR is the difference between the measures of arcs TQ and RQ, so is ...
arc TR = 173° -135° = 38°
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D. Inscribed angle PQR intercepts arc PR, so is half its measure.
angle PQR = 60°/2 = 30°