Answer:
People of various categories are found in cities, out of which 'Upper Class' and 'Lower Class' are two of the categories.
Step-by-step explanation:
There are a number of categories in which an urban population is divided.
The category with the highest income and highest spending capacity is called 'Upper Class. The category with medium levels of income and expenditure is called the 'Middle Class'. The lowest of all categories is the 'Lower Class' which consists of people that have extremely low income and thus, a very low spending capacity.