Question 1041315
The formula in finding the arc length is

{{{s = r*theta}}},

where s = arc length, r = radius, and {{{theta}}}  = angular measure in radians.

Now {{{theta = (4 rev)*((2*pi)/rev) = 8*pi}}}, and radius = diameter/2 = 8 inches.

==> {{{s = r*theta = 8*8pi = 64pi}}} inches.