The two most internationally recognized american writers in the 1820s

a) washington irving and james fenimore cooper.
b) edgar allan poe and charles baudelaire.
c) walt whitman and emily dickinson.
d) herman melville and nathaniel hawthorne.
e) ralph waldo emerson and henry david thoreau.

The correct answer is option A: Washigton Irving and James Fenimore Cooper, were the to most internationally recognized American writers i the 1820s.

Explanation:

Irving was short story writer from New York famously knwon for his work  'Rip Van Winkle' and 'The Legend of Sleepy Hollow. And Fenimore Cooper was who wrote historical romances borned in New Jersey.

is this even a question? ? : /

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.