100/5= 20, 20 seconds is the time needed.
Part a)
Here in this we can use momentum conservation as there is no external force on it

here we know that





now by above equation



Part b)
Final kinetic energy of the system



Initial Kinetic energy of the system will be



So here kinetic energy is decreased for this system
final energy is less than initial energy
Genetically engineering endangered keystone species that are vital to the environment to be more resilient against harmful predators and/or toxins, pathogens, etc.
Answer:
B- the melting of polar ice caps
Explanation:
As the world's temperature increases, polar ice caps will no longer be able to remain solid.