Radius of the circle 5. Find the arc length of the circular sector corresponding to the center angle of 360 degrees.

It would seem that the task is complicated by the fact that you need to determine the length of the arc, not the length of the circle. However, the arc corresponds to a center angle of 360 °, and this angle directly corresponds to the whole circle. That is, it turns out that you need to look for the length of the whole circle, and not one of its parts. The circumference of a circle is equal to twice the product of its radius and the number Pi (when solving problems it is customary to take this number as 3.14, although in some cases rounding even to 3 is required):
2 * 5 * 3.14 = 31.4.
Answer: 31.4.