For example, if you figured 2000 square feet, you need 2000 square feet/100 square feet in a square = 20 squares of slate. A simple roof might be all rectangles (Area = length * width). There are often triangular sections to compute (Area = the base * height/ 2).
The average price for connecting flights from New York to Mexico City is $517. The average price for non-stop flights from New York to Mexico City is $440. The chart below shows up to date information regarding non-stop flights from New York to Mexico City.
The transportation sector has also gone through a major change over the past 50 years. Today, we can travel and ship goods much faster and more cheaply than a half century ago. A round-trip airline ticket from Miami to New Orleans in the early 1960s was $927 (inflation adjusted); it now costs about $330.