X-rays with a wavelength of 0.0711 nm create a diffraction pattern when they pass through a protein

Question:

X-rays with a wavelength of 0.0711 nm create a diffraction pattern when they pass through a protein crystal. If the angular spacing between adjacent bright spots (m = 0 and m = 1) in the diffraction pattern is 28.9°, what is the average spacing between atoms in the crystal?