7. A company faces a potential liability 15 years in the future of an estimated $18 million due to improper disposal of hazardous wastes that may leach into the underlying groundwater. It would like to invest funds now to ensure that it has the needed funds in the future if the contamination does occur. What is the present worth (PW) of this $18 million; that is, what is the amount that should be invested now to ensure that $18 million will be available in 15 years? Assume that the company can get a 12% return on their investment