If the Interplanar Spacing of NaCl Is 2 $\degree$ B)720 $\degree$ C)205 $\degree$

Multiple Choice

If the interplanar spacing of NaCl is 2.814 *10^-10 m,what is the predicted angle at which X-rays of wavelength 0.140 nm will be diffracted in a first-order maximum?

A) 31.3 $\degree$
B) 7.20 $\degree$
C) 20.5 $\degree$
D) 14.4 $\degree$
E) 29.8 $\degree$