The United States and the European Union are groups of semi-independent states that have come together under an agreement whereby resources can travel freely across borders and a common currency is in use. Which of the following statements best explains how this allows for the achievement of economies of scale?
A) Each state or country can now target larger markets and can thus earn more export revenue.
B) States and countries no longer have to worry about borders impeding trade.
C) Each state or country can adopt large-scale production techniques that allow lower per-unit costs of production.
D) The removal of trade borders and a common currency enhances trade between member states.

Suppose that a major city’s main thoroughfare, which is also an interstate highway, will be completely closed to traffic for two years, from january 2014 to december 2015, for reconstruction at a cost of $535 million. if the construction company were to keep the highway open for traffic during construction, the highway reconstruction project would take much longer and be more expensive. suppose that construction would take four years if the highway were kept open, at a total cost of $800 million. the state department of transportation had to make its decision in 2014, one year before the start of construction (so that the first payment was one year away). so the department of transportation had the following choices: (i) close the highway during construction, at an annual cost of $267.5 million per year for two years. (ii) keep the highway open during construction, at an annual cost of $200 million per year for four years. now suppose the interest rate is 80%. calculate the present value of the costs incurred under each plan.