Helium-Neon Laser Light (L = 632

Helium-neon laser light (l = 632.8 nm) is sent through a single slit of width 0.30 mm.What is the width of the central maximum on a screen 1.0 m in back of the slit? (1 nm = 10^-9 m)

A) 2.0 mm
B) 3.1 mm
C) 4.2 mm
D) 5.3 mm