All countries where the national diet is rich in wheat bran are countries where the incidence of colon cancer is low. No countries identical to Canada are countries where the national diet is rich in wheat bran. Therefore, no countries identical to Canada are countries where the incidence of colon cancer is low. Invalid, illicit major 12. All persons who think Africa is in North America are persons with no knowledge of geography.
Some college students are persons who think Africa is in North America.
Therefore, some college students are persons with no knowledge of geography. All diseases carried by recessive genes are diseases that can be inherited by offspring of two carriers. All diseases identical to cystic fibrosis are diseases carried by recessive genes. Therefore, all diseases identical to cystic fibrosis are diseases that can be inherited by offspring of two carriers. No metals identical to cadmium are metals identical to mercury.