Why was the American Federation of Labor a different type of labor union
(compared to the Knights of Labor)
and why did it grow during the 20th
century?

Labor unions arose in the nineteenth century as increasing numbers of Americans took jobs in factories, mines, and mills in the growing industrial economy.

The Knights of Labor, founded in 1869, was the first major labor organization in the United States. The Knights organized unskilled and skilled workers, campaigned for an eight hour workday, and aspired to form a cooperative society in which laborers owned the industries in which they worked.

The Knights’ membership collapsed following the 1886 Haymarket Square riot in Chicago. By 1886 the American Federation of Labor (AFL), an alliance of skilled workers’ trade unions, was growing.

b) a state law could be declared illegal if it contradicted the constitution.

explanation:

the conflict of this case originated when james w. mcculloch, a cashier of the baltimore branch of the second bank of the united states that the congress had chartered in 1816, refused to pay a tax imposed by the maryland state.

in the case, the state of maryland appealed that the establishment of a second bank was unconstitutional since the constitution didn't say anything about granting that power to congress. however, the case determined that even if such right wasn't specifically stated in the constitution, it was part of the "implied powers" of the government enunciated in article i, section 8.

the case also eliminated maryland's legislation to impose taxes to a national bank, asserting that even though the states retained the power of taxation, the constitution's laws are supreme and can not be controlled by the states, therefore, if a state law contradicts the constitution, it should be declared illegal.

explanation:

to extend a country’s power and influence