Crystals can be classified into how many basic crystal systems?

Statement $1$: Graphite is an example of a tetragonal system.
Statement $2$: For a tetragonal system,$a = b \neq c$,$\alpha = \beta = 90^o$,$\gamma = 90^o$.

Where are the constituent particles located in an end-centered unit cell?

The triclinic unit cell has the following parameters:

State the characteristics of a crystal lattice.

$Assertion (A)$: White tin is an example of a tetragonal system. $Reasoning (R)$: For a tetragonal system, $a=b=c$ and $\alpha=\beta=\gamma \neq 90^{\circ}$. The correct answer is