Answer:
Another effect of the spread of Islam was an increase in trade. Unlike early Christianity, Muslims were not reluctant to engage in trade and profit; Muhammad himself was a merchant. As new areas were drawn into the orbit of Islamic civilization, the new religion provided merchants with a safe context for trade.
If the price of Sprite increases, the demand for a substitute good like 7-up will increase too, because people will seek for a substitute product to replace Sprite.
<u>Law of demand</u> explains the higher the price of a good, the less people will demand it (or avoid it), and will seek others to replace it.
Generally, there were two major factors that led to the decline of the Yuan Dynasty: one was the class conflict caused by the heavy taxation, the other one was the ethnic contradiction resulting from the 'Four Class System'. ... Also, power struggles within the ruling class became more and more serious.
