we are given
radius is 1
[tex] r=1 [/tex]
we have angle as
[tex] \theta=\frac{\pi}{2} [/tex]
now, we can use arc length formula
[tex] l=r*\theta [/tex]
where
l is arc length
theta is angle
now, we can plug value
[tex] l=1*\frac{\pi}{2} [/tex]
so,
Exact form:
[tex] l=\frac{\pi}{2} [/tex]............Answer
Decimal form:
[tex] l=1.57 [/tex]............Answer