3c.Consider the interference pattern produced by two slits of width a and separated by a distance d, where d = 3a. The slits are illuminated by normally incident light with wavelength one fifth the slit separation (Lambda=d/5). (c) If the wavelength is large enough, then there will be no minima in the single slit diffraction intensity for theta belongs to closed interval [-90,90] Determine the required wavelength. Express your answer in terms of the slit width, a