Answer:
Radius AC=12
Explanation:
AB is a tangent to circle c so the tangent AB is perpendicular to the radius at A.
Then triangle ABC is right triangle at A.
So by Pythagoras theorem,
CB^2=AB^2 + AC^2
37^2= 35^2 + AC ^2
1369=1225 + AC^2
AC^2= 1369-1225= 144
AC=radical AC^2 =radical 144=12
Hope this helps...
(Note: ^ means power)