Formula for the circumference of a circle:
C = πd or C = 2πr
[C = circumference π(pi) d = diameter r = radius(half the diameter)]
You know:
d = 5 feet
and you're using 3.14 for π, so substitute/plug it into the equation
C = πd
C = (3.14)(5)
C = 15.7 feet Your answer is B