Which scientist proposed a link between contaminated water and cholera? a.) curie b.) koch c.) salk d.) pasteur

Answer is Koch.

Cholera is an acute type of diarrheal illness that affected millions of people around the world over the centuries. Vibrio cholerae is the causative bacterium of the disease. It is transmitted by drinking contaminated water of food with vibrio cholerae. The source of the contamination is usually the feces of an infected person or water contaminated with sewage.  

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

lesson summarykaryotypes a genome is the full set of all the genetic information that an organism carries in its dna. chromosomes arebundles of dna and protein found in the nucleus of a eukaryotic cell.