7) Given angle is 57 degrees. Find angle ABC.

The diagram shows an inscribed angle $$\angle ABC$$. The angle 57 degrees is marked as the measure of the arc AC.

The formula for an inscribed angle is:

$$\angle ABC = \frac{1}{2} \times \text{measure of arc } AC$$

Given that the measure of arc AC is 57 degrees:

$$\angle ABC = \frac{1}{2} \times 57^\circ = 28.5^\circ$$.

The text below the diagram states "ABC - вписанный", which means ABC is an inscribed angle.

Ответ: 28.5°