the complete question in the attached figure
we know that
the length of the circumference (L)=2*pi*r
r=8 ft
so
L=2*pi*8=16*pi ft
the length of arc CD is 35°-------->let's transform the degrees to feet
we apply a rule of three
if 360° -----------------> 16*pi
35°---------------X
X=35*16*pi/360--------> 4.88 ft
the answer is 4.88 ft