A diffraction grating that has 500 lines per mm is employed to study the diffraction of monochromatic light with wavelength $600\,\text{nm}$. The light is first sent through a narrow slit, and the grating is positioned so that its lines run parallel to the slit. The light then travels through the slit and afterwards through the grating. An observer looks at the slit through the grating at a range of angles, shifting his head from X parallel to the grating, via Y, opposite the slit, to Z parallel to the grating on the far side. How many images of the slit does he see?
- A3
- B4
- C6
- D7