As a result of dna testing, scientists learned the black death was

a. the pneumonic plague, not the bubonic plague

b. both the pneumonic plague and the bubonic plague.

c. caused by fleas on cats and dogs.

d. caused by fleas on rats and vermin.

in mcculloch v. maryland (1819) the supreme court ruled that congress had implied powers under the necessary and proper clause of article i, section 8 of the constitution to create the second bank of the united states and that the state of maryland lacked the power to tax the bank.

gibbons v. ogden, (1824), was a landmark decision in which the supreme court of the united states held that the power to regulate interstate commerce, granted to congress by the commerce clause of the united states constitution, encompassed the power to regulate navigation.

it increase by 12% a year from 1812-1820

most people now work in jobs where they do one  kind  of work; they are carpenters, bankers, cooks, mechanics, and so forth. likewise, most  businesses produce  only certainkinds  of  goods  or  services, such as cars, tacos, or gardening  services. this feature of  production  is known as specialization.

to protest slavery i would think it would be a