A Diffraction Grating Has $6.00 \times 10 ^ { 3 }$

Multiple Choice

A diffraction grating has $6.00 \times 10 ^ { 3 }$ lines per centimeter ruled on it. What is the angular separation between the second and the third orders on the same side of the central order when the grating is illuminated with a beam of light of wavelength $550 \mathrm {~nm}$ ?

A) $50.5 ^ { \circ }$
B) $40.6 ^ { \circ }$
C) $30.5 ^ { \circ }$
D) $20.5 ^ { \circ }$