Technically yes you are i think

Explanation:
Given:


The cross product
is given by



If Fg=mg=ma and, Fg(planetX)=1/5Fg(earth)
then the time would be 5x of the time as gravity is acceleration. So 3.9s*5=19.5s
As the force of gravity is less, then the acceleration of masses is also less, therefore it will take more time for the object to fall by the factor of the force of gravity difference
The energy stored by a system of capacitors is given by

where Ceq is the equivalent capacitance of the system, and V is the voltage applied.
In the formula, we can see there is a direct proportionality between U and C. This means that if we want to increase the energy stored by 4 times, we have to increase C by 4 times, if we keep the same voltage.
Calling

the capacitance of the original capacitor, we can solve the problem by asking that, adding a new capacitor with

, the new equivalent capacitance of the system

must be equal to

. If we add the new capacitance X in parallel, the equivalent capacitance of the new system is the sum of the two capacitance

and since Ceq must be equal to 4 C1, we can write

from which we find