Question

http://prntscr.com/6cs81f

Answer 1

Area = pi * r^2 or area = 1/4 pi*d^2

Answer 2

\[A = \pi r^2~~~~\text{or}~~~~A = 1/4 \pi d^2\]

Answer 3

just multiply radius by pie ......so its 11x 3.14

Answer 4

oh ok