1. {El} points} ICoherent light of wavelenglh 420 nm is incident on a single slit of 1width {1.4315 mm. A screen is placed 5 n1 behind lhe single slil. Unlike most of The examples in class, this screen has a FINITE HEIGHT of 6 111 and is centered on the optic axis fie, it extends 3 111 above and below.r The optic axis}. a.) I ll] points] Find lhe total number of DARK fringes on lhis nite screen. b.) {1D points} Suppose the intensity.r of the incident light is 1 Win12. Find the intensity near lhe top edge of the sore en