Which crystal system has no axis of rotation of symmetry?

Calculate the number of unit cells in $1 \ cm^3$ volume of metal if the volume of one unit cell is $3.448 \times 10^{-23} \ cm^3$.

The total number of Bravais lattice arrangements in different crystal systems is

The three-dimensional graph of lattice points which sets the pattern for the whole lattice is called:

$Assertion (A)$: 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

Which of the following crystals has a unit cell such that $a \neq b \neq c$ and $\alpha \neq \beta \neq \gamma \neq 90^{\circ}$?