Two objects X and Y move directly towards each other. The objects have the same mass. Object X has a velocity of 5.0 m/s to the right. Object Y has a velocity of 3.0 m/s to the left.

Object X and object Y collide and stick together.
What is their velocity after colliding?
A 1.0 m/s to the left
B 1.0 m/s to the right
C 4.0 m/s to the left
D 4.0 m/s to the right

The answer is water molecules are split.cellular respiration and photosynthesis are complement  reactions to each other. these are reverse reactions. in cellular respiration glucose and oxygen yield water and carbon dioxide. so, when respiration begins,  glucose molecules are split. in the opposite reaction - in photosynthesis, carbon dioxide and water yield glucose and oxygen. thus,  when respiration begins, water molecules are split.

He sandals were out in the sun so the got hotter. which is why her feet felt hot.