Are anything that stand for an idea
a. sounds
b. symbols
c. feelings

Symbols fit this very well, as they do not always mean what they show, like an idea put forth by a group of people. The Soviet Union had the hammer and sickle to represent hard work and strict government. The US has the Stars and Bars. 

Symbols are anything that stand for an idea . Hope this helps :-)

Because without physical activity, the body has extra "energy" if you will, and so when it is time for bed you are not tired, so you end up staying up all night. also there is probably an effect on your internal clock, which messes with your melatonin production which goes hand in hand with your sleep cycle

Little kids are eat dirt all the time so im sure you are fine