INtensity relationship and bragg reflections

Barium titanate BaTiO3 crystallizes in such a structure that the Ba atoms sit at the corners of a cube with a Ti atom at the cubes center and the O atoms in the ceneters of its faces. Determine the intensity relationship between the first four Bragg reflections with the help of the structure factor. The following form factors apply

$$\begin{gathered} f_{Ba}=7f_O \\ {f}_{Ti}=3f_O \end{gathered}$$

Vad är skillnaden mellan form och structure factor och hur ska jag lösa uppgiften? Är helt borta