Answer:
12.56 miles
Step-by-step explanation:
[tex]l = \frac{ \theta}{360 \degree} \times 2\pi \: r \\ \\ = \frac{ 90 \degree}{360 \degree} \times 2 \times 3.14 \times 8 \\ \\ = \frac{ 1}{4} \times 16 \times 3.14 \\ \\ = 4 \times 3.14 \\ = 12.56 \: miles[/tex]
Hence, length of arc = 12.56 miles
