1. The spreadsheet problem set below is a hypothetical example of two proposed uses for a coastal area called Gringoland. In Gringoland, a coral reef area will either be protected or mined. A set of costs and benefits is given for a 10-year period. For which discount rates does each project have a positive NPV? For which discount rates does each project have a negative NPV? What can you say about the importance of the choice of discount rate in evaluating whether a project has a positive or negative NPV? Table 1: Project 1: Gringoland Marine Park Table 2: Project 2: Gringoland Coral Mining