The program will ask the user to enter:

'1' to List the cities(and their state abbrev)  from largest to smallest (by their population) with their population

'2'  to List the cities from largest to smallest in terms of population density (show city name, state, density, and landsize)

'3' to List the 10 largest cities by population (include city, stat, and population)

'4' to Chose a city from the List to learn an interesting fact about the city's population (allow the user to select the city from a numbered alphabetical list)