Light is incident normally on two narrow parallel slits a distance of 1.00 mm apart. a screen is placed a distance of 1.2 m from the slits. the distance on the screen between the central maximum and the centre of the n=4 bright spot is measured to be 3.1 mm. a determine the wavelength of light. b this experiment is repeated in water (of refractive index 1.33). suggest how the distance of 3.1 mm would change, if at all.