Maximum possible number of three-dimensional and two-dimensional lattices are respectively:

An element has $BCC$ structure with edge length of unit cell $600 \ pm$. What is the atomic radius of the element?

Which of the following statements is correct?

The crystal system with edge lengths $a \neq b \neq c$ and axial angles $\alpha = \beta = \gamma = 90^{\circ}$ is '$x$' and the number of Bravais lattices for it is '$y$'. $x$ and $y$ are:

In a face-centred cubic $(FCC)$ unit cell,the edge length $(a)$ in terms of atomic radius $(r)$ is:

What is the total number of different types of unit cells in a tetragonal crystal system?