Answer:
D) 140 degrees
Explanation:
Radius is perpendicular to tangent line
Draw DA, construction
DA is an angle bisector, m<BAD = 20,
Now, DBA and DCA are congruent right triangles
This is due to LA congruency
90 + 20 + x = 180
x = 70
BDA = CDA
so 70 + 70 = 140
D) 140 degrees
(I'm not that good at geo, so :( )