Three capacitors of capacitance $6\mu F$  are connected in a circuit. Then their maximum and minimum  capacitances will be

Capacitance will be maximum when they are connected in parallel combination

$C_P=3\times 6=18\mu F$

 Capacitance will be minimum when they are connected in series combination

$C_S=\frac{6}{3}\mu F=2\mu F$