Will give brainliest plz help!

Answer:
6.28cm
Step-by-step explanation:
I think for me the easiest would be to find the circumference and divide by 4, since the arc is 1/4 of the circumference of the circle.
C=2πr
C=2(3.14)(4)
C = 25.12cm
25.12cm/4 = 6.28