Answer:
A
Explanation:
option A is correct
the best example of elastic collision among the following is collision between two billiard balls. In collision of two billiard balls the energy lost is very little approximately zero. hence we can say that the kinetic energy is conserved. since, the kinetic energy is conserved we can say that the collision is elastic
Answer:
Reflective
Explanation:
The radiation pressure of the wave that totally absorbed is given by;

and While the radiation pressure of the wave totally reflected is given by;

Now compare the two-equation you can clearly see that the pressure due to reflection is larger than absorption therefore the sail should be reflective.
When the force of the opponent's punch is extended, with time, the effect of the blow or the force of the blow is reduced thereby reducing chances for a knockout punch from the opponent to the boxer.