From the graph that we have here, the event that is responsible for this change is A product becomes less popular and fewer customers purchase it.
The reason this is the answer is because when e look at the graph closely, we can see that only demand fell from 50 to 40. There was no change in price, it remained at 15 dollars.
A fall in demand even at the same price that a good was sold previously shows us that less people are buying the product. This could be due to changing consumer preference.
Read More on brainly.com/question/3748648?referrer=searchResults
a primary source is a source from the time and place of the event, like a photograph that was taken of a president from 1920. If it was something like a book written in 2015 about the picture from 1920, that would be a secondary source. Hope this helps!
