Art needs no justification beyond its own perpetuation.
The question is broad enough to be the topic of an entire book. Let's just say adults, knowingly or not, use math every day of their lives.
Broad refers to a wide scope or inclusiveness in a literary work, covering various themes or characters. Narrow, on the other hand, denotes a more focused or limited aspect of the work, concentrating on a specific topic or storyline.
Example: The man has broad shoulders.
culture
The Broad Ligament. It supports the entire reproductive tract.
culture
acting on conscience or representing the broad interests of the entire society
representative of the people.
There are a number of reasons why you would teach the word thick instead of broad. You may be talking about the layers of Earth for example and broad wouldn't be appropriate.
No, it's not - sneezing is a broad example of MANY symptoms such as a cold for example.
A broad leafed plant.
The question is broad and far-ranging. It would require an entire book to answer thoroughly.