5. [20 pts] Due to pollution, a thin layer (film) of oil (nfilm = 1.4) is deposited on the surface of two different mediums: (a) a standing water (nwater = 1.33) on the ground after rain; and (b) a window glass (nglass = 1.53). A light with wavelength = 550 nm incidents from air (nair = 1.0) almost normal to the oil film. For each case, determine the minimum (i.e. m = 1) thickness of the oil film that results constructive interference for the reflected light rays. (b) V: V Air Air Oil Oil (a) Water Glass