Help with energy conservation calculations

Attention physicists, I need help.

First year university physics student here, and I need assistance finding the kinetic energy of an object (specifically, a mousetrap car our lab team built).
I already found the speed, acceleration, net force, and work, we were given the Ek of the mousetrap spring (100N/cm = 1J), I already know the equation to find Ek (1/2 mv^2), and I know energy is conserved, not created, not destroyed, etc.
The question is, using the values I have, how do I complete the energy conservation calculations?

I can provide data from the trials if needed.

In before "lol failure", it's only a bullshit degree breadth course I'm required to take.

>>10
No >>7 but k is spring constant, x is displacement of spring from equilibrium, int is text shorthand from writing an integral.  If you don't know how integrals work, explaining the rest would be futile.

Yes t is time (it indicates the velocity is non-uniform, but a function of time), and F is force.

These actually are the proper and commonly understood symbols for these terms and concepts.  Nothing obscurist about it.