Channel Tunnel, Inc., plans to build a new 23-mile-long tunnel under the English Channel for added train service. The cost (NINV) of the tunnel is expected to be $3.3 billion. Net cash inflows are expected to equal $651 million per year. How many years must the firm generate this cash inflow stream for investors to earn their required 19 percent rate of return? Please show me how you work the problem so I can properly learn how?