we know that
on an analog clock
60 minutes is equal to a circumference of 360°
so
360/60-----> 6°
that means
1 minute is equal to --------> 6°
16 minutes----------> X
x=16*6-----> 96°
the length of a circumference=2*pi*r
for r=8 in
the length of a circumference=2*pi*8-----> 50.24 in
if 360° (full circle) has a length of----------------> 50.24 in
96°---------------------------> x
x=96*50.24/360------> x=13.40 in
the answer is
13.40 in