Use newtons second law F=ma, plug in the given values which gives us the answer of 22 kg for the mass
Answer:
The time is
Explanation:
From the question we are told that
The period of the circuit is 
Generally voltage maximization of the capacitor occurs during the voltage minimization of the inductor and vise versa
So the time between the voltage maximization of the capacitor and that of the inductor is mathematically represented as

=> 
=>
Just divide the two numbers with each other.
I mean 13/1.4=9.2857...