Answer
Please see the work below.
Work Step by Step
We know that
$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$
This can be rearranged as:
$\frac{V_2}{V_1}=\frac{P_1}{P_2}\times\frac{T_2}{T_1}$
We plug in the known values to obtain:
$V_2=3\times \frac{1}{2}\times V_1$
$V_2=3\times \frac{1}{2}\times V_1$
$V_2=\frac{3}{2}\times 6=9L$
