Answer:
Mass , momentum and mechanical energy
Explanation:
There are two types of collision.
1. Elastic collision: in case of elastic collision no energy is loss in form of heat and sound .
The momentum and the kinetic energy is conserved.
2. Inelastic collision: in case of inelastic or partially elastic collision, some of energy is lost in form of heat or sound. Here momentum and mechanical energy is conserved.
Mass of a system is always conserved.