Answer:
C. 80°, 100°
Explanation:
The only answer choice showing a ratio of 4:5 is choice C.
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A: 80 : 80 = 1 : 1
B: 10 : 80 = 1 : 8
C: 80 : 100 = 4 : 5 . . . . the correct choice
D: 100 : 100 = 1 : 1
For this set of answer choices, you can simply look at the ratio. You don't even need to know what supplementary angles are.