A parallel beam of light (λ=450 nm) is normally incident on a diffraction grating. The lens is located directly behind the grating and projects the spectrum onto a screen 0.5 m away from it. In the diffraction spectrum, the distance between the first order maxima is 12 cm. Determine the diffraction grating constant d, the total number N of maxima in the spectrum, and the angle of deflection of the rays corresponding to the last diffraction maximum.

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