In a double-slit experiment, the slits are illuminated by a monochromatic, coherent light source having a wavelength of 609 nm. an interference pattern is observed on the screen. the distance between the screen and the double-slit is 1.69 m and the distance between the two slits is 0.118 mm. a light wave propogates from each slit to the screen. what is the path length difference between the distance traveled by the waves for the sixth-order maximum (bright fringe) on the screen?