How do you get the answer or what is the answer? I’m confused and the teacher is unavailable. The problem is asking to find the measure of arc ABC. Will give out brainliest

Answer:
60 degrees
Step-by-step explanation:
A trapezoid has a total of 360 degrees and you know m D is 118 so m C will be 118. Added together is 236. subtract that from 360 you get 124 then divided by 2 is 60.
118x2=236 360-236=124 124/2=60