convert 157° to radians and multiply that by 5

2pi * 5 * (157/360) = 13.7ft

L arc = (157/360) x ( 2π x 5 ) ft

L arc = 13 . 7 ft

An arc with radius r and angle θ has the arc length:

s = rθ .... if θ is measured in radians, or

s = (θ/180)πr .... if θ is measured in degrees

Remember those two formulas (or just the second if you haven't studied radians yet.)

You have θ=157° and r=10 ft, so:

s= (157/180)π(5 ft) = 157π / 36 ft

That's exact, if the given measurements are, or about 13.7 ft using a calculator.

The circumference is 10 pi ft.

The specified arc has a length of

(10 pi ft)*(157/360) = 13.7 feet.