a= 34 degrees
b= 28 degrees
c= 62 degrees
Explanation:
First you know that b is 1/2 of 56 degrees or 28.
The triangle with the a in it is isoceles because the two sides are both radii.
In the triangle the top angle = 112 because it is a centeral angle to the 112 arc.
Angle a and opposite to a are equal and then have to be 34 degrees to equal 180.
We know two arc lengths are 112 and 56 and the one with angle a has to be 34x2 or 68.
a whole circle equals 360.
360-56-68-112 = 124
Angle c = 1/2 of 124, or 62 degrees