@oherent violet light (wavelength 350nm) shines through a diHraction grating with many ' closely-spaced slits. The light forms an interference pattern on a screen placed behind the grating, with bright bands separated by distance 3. Which of the following changes to the system will cause the pattern to spread out so that the separation between consecutive bright bands becomes 23? I. Use red light with wavelength 700nm II. Use a smaller grating with half as many slits (but the same separa- tion between consecutive slits) III. Use a grating where the slits are twice as far apart. IV. Move the screen twice as far away behind the grating. A. IV only B. I and III only C. II and IV only 12; I and IV only E; I, II, III, and IV 3. A screen is placed 2.5m from a single slit of width 0.20mm, which is illuminated with coherent yellow light (wavelength 580nm). What is the distance between the first and the second dark minima in the diffraction pattern formed on the screen? Both of the dark bands are on the same side of the center line. A. 15 mm B. 7.2 mm C. 3.6 mm D. 4.9 mm E. 6.5 mm