6a (7 pts). The figure below shows the central part of the interference pattern for a pure wavelength of red light projected onto a double slit. The pattern is actually a combination of single slit and double slit interference. (a) Note that the bright spots are evenly spaced. Is this a double slit or single slit characteristic? (1.5 pts) (b) Note that some of the bright spots are dim on either side of the center. Is this a single slit or double slit characteristic? (1.5 pts) P (c) Which is smaller, the slit width or the separation between slits? Explain briefly with formula. (4 pts) 6b (9 pts). In a double-slit experiment it is found that green light of wavelength 550 nm gives a third-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same location?