If 0.025 eV neutrons were fired through a double slit so that the first order interference occurred at 10°, what is the slit spacing?
a) 1.0 × 10-9 m
b) 2.5 × 10-8 m
c) 1.8 × 10-10 m
d) 3.1 × 10-11 m
e) No answer is correct since neutrons cannot act like waves.