Motorola and other backers sank more than $5 billion in the 1990s into the development of Iridium, satellite communications systems to connect wireless telephone users anywhere on earth. Although the number of subscriber's signing up for the service has fallen significantly below projections and operating costs vastly exceed revenues, this is no reason for Motorola and its partners to back out of the venture. Indeed, it would be foolish to quite now given the large amount of money that has already been invested in Iridium." True, false, or uncertain. Explain.