A 1 kg hockey puck is sliding on the ice at 5m/s and stops on some dirt in 2 secs. I need to find the coefficient of kinetic friction.

I found the acceleration being -2.5m/s^s (0-5m/s / 2s)
Idk what to do next pleaseeee help

Good, so

Frictional force = ma = 1kg (-2.5)m/s²
= -2.5 N

Normal reaction
=mg
=1kg * 9.8 m/s²
=9.8 N

Coefficient of kinetic friction
= Frictional force / Normal reaction
= -2.5 / 9.8
= 0.255 (omit sign).