A laser beam of unknown wavelength shines through the two slits and produces a diffraction pattern with dark bands at y1 = 8.9mm, y2 = 26.7 mm, and y3 = 44.6 mm from the center of the central intensity maximum. If the distance between the slits d = 78 µm, and the distance between the slits and the screen is D = 170cm, what is the wavelength of the laser light used?
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