Answer:
6.3feet
Explanation:
Given data
Radius= 4feet
The expression for the circumference of a circle is
C= 2πr
Substitute
C=2*3.142*4
C=25.136 feet
Also, a 90° arc is 1/4 of the circumference of a circle
Hence the length of the 90° arc is
=25.136/4
=6.284 feet
=6.3feet