Final answer:
Linear momentum is conserved in both an explosion and a collision, while kinetic energy is not conserved in an explosion and may not be conserved in an inelastic collision.
Step-by-step explanation:
The question deals with conservation laws in physics, specifically with linear momentum and kinetic energy during explosions and collisions. When an internal explosion breaks an object into two pieces, the total linear momentum before and after the explosion is conserved, which means it remains zero if the object was initially at rest (statements a and b are correct). However, kinetic energy is not conserved during the explosion – it increases from an initial value of zero (statement c is incorrect).
In a separate scenario where two objects of equal mass collide, and one stops while the other moves after the collision, linear momentum is conserved (because the total momentum before and after the collision remains constant), but kinetic energy is not conserved if one object comes to rest and the other moves (statement b is correct in this case).