Light from a Monochromatic Source Shines Through a Double Slit

Multiple Choice

Light from a monochromatic source shines through a double slit onto a screen 5.0 m away. The slits are 0.18 mm apart. The dark bands on the screen are measured to be 1.7 cm apart. What is the wavelength of the incident light?

A) 457 nm
B) 306 nm
C) 392 nm
D) 612 nm
E) 784 nm