In early 1990, Boeing Co. decided to gamble $ 4 billion to build a new long- distance, 350- seat wide- body airplane called the Boeing 777. The price tag for the 777, scheduled for delivery beginning in 1995, is about $ 120 million apiece. Assume that Boeing's $ 4 billion investment is made at the rate of $ 800 million a year for the years 1990 through 1994 and that the present value of the tax write- off associated with these costs is $ 750 million. On the basis of estimated annual fixed costs of $ 100 million, variable production costs of $ 90 million apiece, a marginal corporate tax rate of 34% and a discount rate of 14%, what is the break-even quantity of annual unit sales over the Boeing 777' s projected 15- year life? Assume that all cash inflows and outflows occur at the end of the year.