Answer:
15.7 km
Step-by-step explanation:
First find the circumference around the circle
C = 2*pi*r
C = 2 *3.14 * 10
62.8
Then find the fraction of the circle the arc is
The arc is 90 degrees and the circle is 360 degrees
90/360 = 1/4
Multiply the circumference by the fraction
1/4*62.8 =15.7
