Diffraction gratings having n = 200 lines per 1 mm is placed on the table of the goniometer. Before slit collimator is a discharge tube with krypton. The light beam emerging from the collimator is incident on the grating perpendicular to its plane. At what angle to the incident beam on the grating is necessary to put the telescope to the field of view coincided with the line of krypton wavelength 556.01 nm and 403.78 nm? In what orders range may occur such a coincidence?

Detailed solution shorthand terms, formulas and laws used in the decision, the withdrawal of the calculation formula and the response.
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