A diffraction grating with 100 lines per mm is used to form a diffraction pattern on a screen that is placed 198 cm from the grating to the screen. The first-order maximum is observed at a distance of 19.8 cm from the central maximum of the pattern. Find the wavelength of the light in nanometers (nm) and report the answer to three significant figures.
The grating line spacing is measured in lines/mm, the distances to the screen and 1st order maximum are in centimeters, and the answer must be written in nanometers (nm).