Which premitive unit cell has unequal edge length `(a != b != c)` and all axial angles different from `90^(º)`?

Which premitive unit cell has unequual edge lengths (anebnec) and all axial angles different from 90^(@) ?

Which premitive unit cell has unequual edge lengths (anebnec) and all axial angles different from 90^(@) ?

Which of the crystal systems has all the axial angles equal but not equal to 90^(@) ?

An element has bcc studture with unit cell edge length of 288 pm. How many unit cells and no. of atoms are present in 200 cm^3 of element?

A unit cell of sodium chloride has four atoms units per unit cell. The edge length of unit cell is 0.564 nm. Find out the density of sodium chloride.