I believe most activity takes place during daylight hours.So the life move fast in day. If we talk about the -Sound. At night , the air is denser due to humidity (obviously nights are cooler). sound requires medium to travel and so DENSER the medium,FASTER the sound travels.
The period of physical changes to sex characteristics that marks the beginning of adolescence in males and females is Puberty.
Note that this is a position vs time graph.
From A to B, the graph is a straight line with a nonzero slope. This indicates a constant velocity.
From B to C, the graph is a straight line with 0 slope. This indicates a constant position, i.e. the object remains stationary.
From C to D, the graph is a straight line with a nonzero slope. This indicates a constant velocity.
Answer: No , a chemical change has not occured as it was easily reversed.
Explanation:
Chemical change is defined as a change in which rearrangement of atoms take place and leads to formation of new substances. It can only be reversed with the help of a chemical reaction.
Physical change is defined as a change which leads to change in shape, size or state of the substance changes. No new substance is formed.It can be easily reversed.
As the hair colour was washed out and returned to its original brown colour, it was a physical change.