Which group of people was most directly affected by the Twenty-Sixth
Amendment?

People 18 year or older. ( Mainly 18, 19, and 20 year olds were affected because previously you could only vote if you were 21 years or older, so the 26th amendment changed that).

Explanation:

Amendment Twenty-sixth to the Constitution of the United States is very significant in the history of constitutional amendments of the United States. This Constitutional Amendment lowered the minimum voting age. Following this amendment, the voting age of American citizens was reduced to 18 from 21. Moreover, this Amendment prevents the federal and the state government from employing age as a reason for rejecting the right to vote to any of the U.S. citizens who is at least 18 years of age.

not sure might be he acquired the entire oregon territory from great britain

your answer is 1930's

explanation

this is just around the time the great depression was starting and putting the us ecnomy into ecnomic failure causing the goverment to take a much larger rule to try and pieace it back together