Answer:
The length of a 180° arc of a unit circle is π ≈ 3.14 units.
Step-by-step explanation:
Use your knowledge of the circumference of a circle (the length full around) and the fact that there are 360° in the central angle of a full circle. The distance around is proportional to the angle, so an arc of measure 180° will have a length equal to
... (180°/360°) × circumference = (1/2)×circumference
For a unit circle, the circumference is 2π (= π×diameter = 2π×radius). Half that length is π units.
