A diffraction grating is placed 1.00 m from a viewing screen. Light from a hydrogen lamp is passed during the grating, and the 656 nm line in the hydrogen spectrum is seen in first order 60.0 cm to one side of the center. Then the hydrogen lamp is replaced by a mercury lamp.
I) where does the first order 546 nm lines in the mercury spectrum fall on the screen?
II) A firs order spectral line is seen on the screen 36.4 cm away from the center what is the wavelength?