Answer:
The length of the arc is 4.6375 miles
Explanation:
Firstly, find the perimeter of the circle by doing 2*pi*r, you'll get about 18.55 miles.
2*pi*r ---> 2*pi*3 ---> 6*pi ---> ≈ 18.55 miles
Next, plug in x/360, where 360 is the total arc of a circle, and x is the arc you need.
x/360 ---> 90/360 ---> = 0.25
Lastly multiply the two numbers.
18.55 * 0.25 ---> 4.6375 miles is your answer.
(you may need to round your answer if needed)