An 18-Mm Wide Diffraction Grating Has Rulings of 880 Lines

Multiple Choice

An 18-mm wide diffraction grating has rulings of 880 lines per mm.Monochromatic light of 590 nm wavelength is incident normally on the grating.What is the largest angle,measured from the central bright spot,at which an intensity maximum is formed?

A) 31°
B) 29°
C) 27°
D) 25°
E) 23°