5) Knowing that the refractive index for silicon is 3.9 and silicon cell thickness is 0.1 um. For an anti-reflection coating on the silicon cell with refractive index of 1.9 and a thickness of 60 nm, at which wavelength destructive interference will occur for the reflected light? A ) = 456 nm B. 1 = 228 nm C. 2 = 780 nm D. A = 1560 nm