Which of the following is not an example of a perfectly inelastic collision?

$A$ bag of mass $M$ is suspended by a string. $A$ bullet of mass $m$ moving with velocity $v$ enters the bag and gets embedded in it. Then,for the system:

$A$ scooter of $40\,kg$ mass moving with velocity $4\,m/s$ collides with another scooter of $60\,kg$ mass moving with velocity $2\,m/s$ in the same direction. After the collision,the two scooters stick to each other. The loss in kinetic energy is .............. $J$.

$A$ bullet is fired from a gun. It hits a solid block resting on a frictionless surface,gets embedded into it,and both move jointly. In this process,

$A$ body of mass $3 \ kg$ moving with a velocity $(2 \hat{i}+3 \hat{j}+3 \hat{k}) \ m/s$ collides with another body of mass $4 \ kg$ moving with a velocity $(3 \hat{i}+2 \hat{j}-3 \hat{k}) \ m/s$. The two bodies stick together after collision. The velocity of the composite body is

Two identical masses $M$ moving with velocities $\mu_1$ and $\mu_2$ collide perfectly inelastically. The loss in energy is