Question

Find the value of each variable. for each circle, the dot represents the center

Answer 1

we know that
The inscribed angle measures half of the arc it comprises.
Opposite angles in a cyclic quadrilateral add up to 180°

Part 1)
a=360-(128+134)-------> a=98°
b=a/2--------> b=98/2----> 49°

the answer Part 1) is
a=98°
b=49°

Part 2)
92+d=180--------> d=180-92-------> d=88°
102+c=180-----> c=180-102----> c=78°
140+a=102*2-----> a=204-140-----> a=64°
b+a=2*d------> b+64=2*88-----> b=2*88-64----> b=112°

the answer Part 2) is
a=64°
b=112°
c=78°
d=88°