Answer:
17. C 60°
18. D 121°
Step-by-step explanation:
The external angle is half the difference of the intercepted arcs.
17. (161° -41°)/2 = 60°
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18. (? -59°)/2 = 31°
? = 59° +2(31°) = 121°
B?, lmk if it's wrong lol