A) What is the ratio of the slit width to the wavelength of the incident light? B) What is the wavelength of the incident light, in nanometers? C) If the screen is very wide, how many dark bands appear to one side of the central maximum?

In a single-slit diffraction experiment, a coherent light source illuminates a slit in a barrier, and the resulting pattern is projected on a screen that is separated from the barrier by a distance which is very large as compared to the slit width and the wavelength of the light source. A light sensor is used to measure the intensity of the light at the screen, and a student makes a graph, as shown below, of the intensity as a function of the position along the screen as measured from the center of the central maximum. The intensity of the central maximum is reduced by a factor of 10 relative to the other maxima to make the graph more easily readable. The distance from the barrier to the screen is 2.2 m, and the light source has a wavelength of 565 nm.