Two billiard balls, each with a mass of 0.17 kg, collide with each other on a pool table. Before the collision, one ball is moving south at 2.8 m/s and the
other ball is moving north at 1.6 m/s. What is the momentum of this system
after the collision?
A. 0.20 kg. m/s north
B. 0.20 kg m/s south
C. 0.60 kg m/s south
D. 0.60 kg: m/s north

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

The law of the conservation of momentum says that the total momentum of any closed and isolated system cannot

Describe how the motion of a spring being pushed forward and backward is similar to the motion of air particles in a sound wave.