A diffraction pattern of a cubic crystal of lattice parameter a = 3.16 is obtained with a monochromatic x-ray beam of wavelength 1.54 . The first four lines on this pattern were observed to have the following values: Line e (in degrees) 1 20.3 29.2 3 36.7 4 43.6 Determine the interplanar spacing and the Miller indices of the reflecting planes.