A pair of slits separated by 1.3 mm, are illuminated with monochromatic light of wavelength 573 nm. The light falls on a screen 1.18 m away producing an interference pattern. A piece of glass with index of refraction n = 1.63 is placed at one slit. Placing the piece of glass in front of the slit causes the maxima to shift 0.17?x, where ?x is the distance between adjacent maxima. What is the thickness of the glass in ?m?