What makes some collisions elastic and others inelastic?

If the collision involves bouncing, it is elastic.

If the collision involves sticking together, it is elastic.

If there is no loss of kinetic energy in the collision, it is inelastic.

If there is energy lost in the collision to sound, heat, etc., the collision is inelastic.

Neurons are components of the nervous system of the body that transmit signals as electrical impulses travel along their length. these impulses propagate when charge suddenly rushes into and then out of a part of the neutron called an axon. measurements have shown that, during the inflow part of this cycle approximately 5.6x10^11 na per meter, each with a charge of e enter the axon. how many coulombs of charge enter a 1.10 cm length of axon during this process