What is the measure of

Answer:
Angle A is 37 degrees, Angle B is 82 degrees, Angle C is 61 degrees
Step-by-step explanation:
Exterior angles are the supplement of interior angles, so subtract 143 from 180 to find Angle A.
180 - 143 = 37
All angles add up to 180.
37 + 61 = 98
180 - 98 = 82
Angle B is 82 degrees.
Hope this helped. :)