Why should drinking water be pure and clean

Americans often refer to a country that is not the united states as a

Around the third week of a college class, a professor decides she’s had enough, is tired of dealing with bureaucracies, and wants out. so one day, instead of coming to class, she flies to tahiti and sells souvenirs on the beach. if this happened, the college would simply assign a substitute to finish the course. what does this tell you about the nature of the authority wielded by a professor?

Why would it be hard to live in a city state