he circle shown below has AB and BC as its tangents: AB and BC are two tangents to a circle which intersect outside the circle at a point B. If the measure of arc AC is 160°, what is the measure of angle ABC? (1 point) 80° 40° 60° 20°

A quadrilateral has a sum of interior angles equal to 360.

Angle A & C are each 90 degrees, and we're given that AOC (arc AC) is 160 degrees.

Therefore
angle ABC=360-160-90-90=20 degrees