1) Given angle is 70 degrees. Find angle ABC.

In a circle, the inscribed angle is half of the central angle that subtends the same arc. The angle given is 70 degrees, which is the angle subtended by the arc AC at point B (an inscribed angle). Therefore, the arc AC measures 2 * 70 = 140 degrees.

The question asks for angle ABC. However, the image indicates that angle ABC is given as 70 degrees. The calculation shown suggests that angle ABC = 1/2 * arc AC = 1/2 * 70 = 35 degrees, which contradicts the given information. It is likely that the 70 degrees refers to some other angle or arc, or there is a misunderstanding in the notation. Assuming that the diagram implies that angle AOC (central angle) is 70 degrees, then angle ABC (inscribed angle) would be 35 degrees. If 70 degrees refers to inscribed angle ABC, then the answer is simply 70 degrees.

However, if we consider the written text below the diagram, it states "

Ответ: 35°