Given:
Radius = 16 inches
right central angle = 90°
I am assuming that we are looking for the length of the arc EF.
First, compute for the circumference of the circle.
C = 2 r π
C = 2 (16) π
C = 32 π
Second, divide the circumference by 4.
360 / 90 = 4
32 π / 4 = 8 π
The length of arc EF is 8 pi inches.
