The first order diffraction from (110) plane of KCl observed using X-ray of wavelength 150 pm and edge length of unit cell is 305 pm, then glancing angle is equal to -
[sin 20.35° = 0.3478
sin 38.35 = 0.6205
sin 40.35° = 0.6475
sin 18.35 = 0.3148]
1
38.35°
2
20.35°
3
40.35°
4
18.35°