A laser beam is directed normally at a transmission diffraction grating to calibrate a spectrometer. The grating has 3.50×105 lines m−13.50 \times 10^5\text{ lines m}^{-1}3.50×105 lines m−1. The total angular separation between the two third-order diffraction maxima is 82.0∘82.0^\circ82.0∘.
What is the wavelength of the laser light?
469 nm469\text{ nm}469 nm
625 nm625\text{ nm}625 nm
719 nm719\text{ nm}719 nm
943 nm943\text{ nm}943 nm
