I normal bubble starts at the speed of 10mph then speeds up +5 each second. so this would be 600 meters. also, it depends on the density of the water and whats inside the water or liquid in the lake. there are many factors that will change this speed.
Answer:
The energy stored in the capacitor quadruples its original value.
Explanation:
The energy stored in a capacitor is given by the equation

where
C is the capacitance
V is the voltage across the plates
The capacitance, C, depends only on the properties of the capacitor, so it does not change when the voltage applied is changed.
Instead, in this problem the voltage applied is doubled:
V' = 2V
So the new energy stored is

so, the energy stored has quadrupled.