Answer:
a= 30
b= 60 (pretty sure)
c=105
Explanation:
a is a vertical angle to 30, so that means it is also equal to 30.
To find b, since it's on a straight line, you can add up the angles in the triangle and solve for b.
30+90=120
120+b=180
b=60
To find c, you subtract 75 from 180 since it's also a straight line equal to 180 degrees.