56. A small helium-neon laser emits red visible light with a power of 3.0 m W in abeam with a radius of 2.0 mm. Which of the following values is closest to theelectric field amplitude of this light in V/m? (ε0=8.85 x10-12 C/N·m2)
(A)0.8
(B)5.0
(C)30
(D)400
(E)1000