Go through the list of choices. Add up the angles. If the result is 180, then we have the answer
A) 60+45+70 = 175, which isn't 180 so we scratch this off the list
B) 30+85+25 = 140, also doesn't work
C) 55+90+35 = 180, we found the answer
D) 110+15+45 = 170, doesn't work
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In summary, the answer is choice C) 55 degrees, 90 degrees, 35 degrees
