#### Answer

We can rank the potential difference from largest to smallest:
$\Delta V_3 \gt \Delta V_1 = \Delta V_4 \gt \Delta V_2$

#### Work Step by Step

We can write an expression for the potential difference in each case:
$\Delta V_1 = \frac{Q}{C}$
$\Delta V_2 = \frac{Q}{2C} = \frac{1}{2}\times \frac{Q}{C}$
$\Delta V_3 = \frac{2Q}{C} = 2 \times \frac{Q}{C}$
$\Delta V_4 = \frac{2Q}{2C} =\frac{Q}{C}$
We can rank the potential difference from largest to smallest:
$\Delta V_3 \gt \Delta V_1 = \Delta V_4 \gt \Delta V_2$