Kinetic energy because there is motion (PE converting to KE). Potential energy is the amount of stored energy.
The acceleration of body is given 16.3m/s2 and the force is given 4.6 N then
We know,
Force=mass*acceleration
Then,
Mass=force/acceleration
Mass=4.6/16.3
Mass=0.28kg
The mineral with Mohs hardness would be scratched because the mineral with Mohs 7 hardness is stronger than the Mohs 5 mineral. Eventually, that mineral would turn into dust if you kept rubbing it.