Answer:
pi/6
Explanation:
the full arc of the circle is the circumference = 2pi×r.
since r = 1, we get circumference = 2pi.
the full arc of 2pi is for 360° or 2pi radians (hence the definition).
an angle given in radians for the norm circle with radius = 1 IS therefore already the arc length for that angle.
for 2pi the arc length is 2pi.
for pi/6 the arc length is ... pi/6.