DELTA P=\frac{4T}{r}\ \Rightarrow \frac{\Delta {{P}_{1}}}{\Delta {{P}_{2}}}=4\]\[\therefore \ \frac{{{r}_{2}}}{{{r}_{1}}}=4\] and \[\frac{{{V}_{1}}}{{{V}_{2}}}={{\LEFT( \frac{{{r}_{1}}}{{{r}_{2}}} \right)}^{3}}=\frac{1}{64}\]