Answer:
QS ≈ 4.71 units
Step-by-step explanation:
The arc QS is calculated as
QS = circumference of circle × fraction of circle
= 2πr × [tex]\frac{90}{360}[/tex] ( r is the radius )
= 2π × 3 × [tex]\frac{1}{4}[/tex]
= 6π × 0.25 ≈ 4.71 units ( to the nearest hundredth )