A laser beam is incident normally on a diffraction grating with 3.00×105 lines m−13.00 \times 10^5 \text{ lines m}^{-1}3.00×105 lines m−1. The total angular separation between the two third-order diffraction maxima is 70.0∘70.0^\circ70.0∘.
What is the wavelength of the laser light?
522 nm522 \text{ nm}522 nm
637 nm637 \text{ nm}637 nm
910 nm910 \text{ nm}910 nm
1040 nm1040 \text{ nm}1040 nm
