A Certain Crystal Has a Spacing of 0

Multiple Choice

A certain crystal has a spacing of 0.442 nm between atoms.A beam of neutrons moving with a speed of 1640 m/s perpendicular to the surface is diffracted as it passes through the crystal.What is the angle from the central maximum to the next interference maximum? (m_neutron = 1.675 × 10^-27 kg,h = 6.626 × 10^-34 J ∙ s)

A) 17.0°
B) 21.0°
C) 33.1°
D) 60.0°
E) 90.0°