1. All dolphins are polar bears. Therefore, it is false that no dolphins are polar bears.

2. It is false that some recessions are not periods of economic decline. Therefore, it is false that no recessions are periods of economic decline.

3. It is false that some suicide survivors are comeback kids. Therefore, some suicide survivors are not comeback kids.

4. It is false that some ruby earrings are not pieces of jewelry. Therefore, some ruby earrings are pieces of jewelry.

5. It is false that all visitors to Rio are Carnival addicts. Therefore, no visitors to Rio are Carnival addicts.

6. Some tax cheats are not honest citizens. Therefore, no tax cheats are honest citizens.

7. All truthful lies are curious assertions. Therefore, some truthful lies are curious assertions.

8. It is false that no bankrupt hair salons are thriving enterprises. Therefore, all bankrupt hair salons are thriving enterprises.

9. It is false that some functional skateboards are not devices equipped with wheels. Therefore, all functional skateboards are devices equipped with wheels.

10. Some film directors are artistic visionaries. Therefore, some film directors are not artistic visionaries.