The question is incomplete, here is the complete question:
Solid cesium iodide has the same kind of crystal structure as CsCl which is pictured below: If the edge length of the unit cell is 456.2 pm, what is the density of CsI in 
The image is attached below.
<u>Answer:</u> The density of CsI is 
<u>Explanation:</u>
To calculate the density of metal, we use the equation:

where,
= density
Z = number of atom in unit cell = 2 (BCC)
M = atomic mass of CsI = 259.8 g/mol
= Avogadro's number = 
a = edge length of unit cell =
(Conversion factor:
)
Putting values in above equation, we get:

Hence, the density of CsI is 