In a certain building construction project , 6500 feet of ductwork is required. Today's price of a 24-inch diameter duct is 127.50$ per foot. If the cost of the ductwork is expected to increase 7% per year into the foreseeable future. What is the total ductwork cost going to be in a new construction requiring 15,000 feet of 24-inch diameter ductwork 15 years from now?

Consider the One Laptop per child project pioneered by a team of engineers from M.I.T. This computer will be sold in remote parts of the world(e.g. rural Cambodia and Nepal) for 55$ apiece. A reputable laptop manufacturer has been contracted to build the laptops at variable cost of 54.85$ per machine, plus a fixed tooling cost of 7.5$ million.

(a) How many laptops must be sold for this humanitarian effort to be profitable?

(b) If the estimated market size in 2009 was 150$ million students and they sold laptops to only 45% of these students, how much money would the One Laptop per Child project lose (or gain) this effort?