If the average price of regular bottled water falls to $0.65, consumers will demand fewer bottles of premium water at every price, which shifts the demand curve for premium bottled water to the left.
Out of three conditions that Donald Noel suggest in "Noel Hypothesis", which are ethnocentrism, competition and the differential in power ethnic or racial, I think the most important is competition. Human beings create ranks in ethnic groups by competing. For example when Irish came to America (1820-1860), they competed with other group to gain positions in society and some of them followed the bad way creating the Irish mob and some entered the police force which gave this group a better status then the Italian mob overcome the Irish mob. It is just an example of how ethnic groups compete to survive and society moves into stratification.
I think there is power and inequality between groups and this leads to prejudice and discrimination. The groups that are suffering more are vulnerable groups like women, elderly and children. Here is Peru there is a great problem with women being killed. It is insane but the number of these cases is going up every year. When women go to the police station do denounce their partners, police officers don't pay them attention to what they say and in many cases they don't do anything. Most of the time women are killed by their partners in Peru. Women are afraid to denounce their partners too.
Africa the world’s second largest continent evolved from nomadic tribes to sedentary communities and then to powerful empires. Ghana, Mali, and Songhahi were all empires that relied heavily on trade of salt and gold, powerful militaries, and Islamic influence to become powerful empires.Ghana became a powerful state when it gained control of valuable trade routes with the help of a strong military.The empire of Mali reached its height under the ruler Mansa Musa, but the empire fell to invaders in the 1400s.The Songhai built a new Islamic empire in West Africa, conquering many of the lands that were once part of Mali.
He was a democrat. Hope this helps!