# In a monoclinic unit cell , the relation of sides angles are respectively :

$(a)\;a = b \neq c \;and\; \alpha=\beta=\gamma=90^{0} \qquad(b)\;a \neq b \neq c \;and\; \alpha=\beta=\gamma=90^{0} \qquad(c)\;a \neq b \neq c \;and\; \beta=\gamma=90^{0} \neq \alpha\qquad(d)\;a \neq b \neq c \;and\; \alpha \neq\beta \neq \gamma \neq 90^{0}$