A laboratory requires the central diffraction maximum produced by a single slit to have a linear width of 8.0mm on a screen 2.0m away when illuminated with monochromatic light of wavelength 500nm.
(i) Calculate the slit width that should be chosen to meet this requirement.
(ii) If the same slit is illuminated with light of wavelength 400nm, find the new linear width of the central maximum on the same screen.