3. 6.21 For each of the following scenarios, state whether an incremental investment analysis is required to select alternative X or Y, and state why or why not. Assume that alternative Y requires a higher initial investment than X and that the MARR is 19% per year.

1. X has an ROR of 28% per year and Y has an ROR of 19% per year.

2. X has an ROR of 18% per year and Y has an ROR of 23% per year.

3. X has an ROR of 16% per year and Y has an ROR of 19% per year.

4. X has an ROR of 30% per year and Y has an ROR of 23% per year.

5. X has an ROR of 21% per year and Y has an ROR of 22% per year.

6. X has an ROR of 18% per year and Y has an ROR of 17% per year.