In a double-slit experiment, light from two monochromatic light sources passes through the same double slit. The light from the
first light source has a wavelength of 645 nm. Two different interference patterns are observed. If the 8th order bright fringe from the first light source coincides with the 9th order bright fringe from the second light source, what is the wavelength of the light coming from the second monochromatic light source?