can you guys help me with this one problem? Thanks a bunch!

Problem:
Draw a circle whose center is at (1,2) so that the point (1,5) is a point on the circle. What is the circumference of the circle.
I don't get this so please help!!!

the radius of the circle is √(0^2 + 3^2) = 3

circumference is 2pi*r = 6pi