Final answer:
Given that line AD is tangent to circle E with an angle measure of 110°, and arc CB measures 120°, we use these to find arc CBA's measure. However, calculations reveal that the measure of arc CBA is 10°, which doesn’t match with the provided answer options.
Step-by-step explanation:
The question involves finding the measure of arc CBA given that line AD is tangent to circle E, and the measure of angle DAB is 110°. Knowing that the measure of minor arc CB is 120°, we can determine the measure of arc CBA. Since angle DAB is the external angle to the circle and AD is the tangent, angle DAB is equal to the difference between the measures of the minor arcs CB and CBA. Thus, the measure of angle DAB (110°) is equal to the difference between the measure of minor arc CB (120°) and arc CBA.
We can set up the equation:
Measure of angle DAB = measure of arc CB - measure of arc CBA
110° = 120° - measure of arc CBA
Measure of arc CBA = 120° - 110°
Measure of arc CBA = 10°
However, none of the answer choices match this result. We may need additional information to determine why our calculation differs from the provided answer options or we might have interpreted the question incorrectly. Additional details or clarification from the student might be needed.