Answer:
c = 56 deg
Explanation:
We can see that two straight lines intersect each other. This means that vertical angles are present. The angle opposite to 124 deg will be equal to 124 deg. So, b + 90 deg = 124 deg. This means that
b = (124-90) deg
= 34 deg
(b+90 deg) and c are supplementary, meaning that they add up to 180 deg.
b+90 deg + c = 180 deg
124 deg + c = 180 deg
c = 56 deg