Answer:the average kinetic energy is directly proportional to the temperature . When water freezes, the temperature decreases and therefore, the average kinetic energy will also decreases as well.
Explanation:
It would be both speed and direction depending on the man's swing
As we know that as per Newton's II law we have

here we will have
= change in momentum
= time interval in which momentum is changed
now in order to have least injury during jumping we need to have least force on the jumper
so in order to have least force we can say that the momentum must have to change in maximum time so that amount of force must be least
So we need to increase the time in which momentum of the system is changed