The main goal of those who participated in freedom summer was to

register blacks to vote in the South.

Explanation:

Freedom Summer was a major civil rights campaign that started in mid-1964, with the objective to register as many blacks as possible to vote in the South, particularly in the state of Mississippi. Racial segregation in the South, especially through the Jim Crow laws, had barred black people from exercising their full civil rights, including the right to vote. Freedom Summer was launched as response to that, and many volunteers, black and white, joined the initiative. However, it wasn't well received by a large part of the white population, and activists were subject to harassment and violence from the authorities and the public alike. Because of this and resistance to change, Freedom Summer wasn't succesful in registering many blacks to vote, but it brought attention to the issue, and it was a major influence behind the Voting Rights Act of 1965, which finally granted universal suffrage in the United States, regardless of race.

the best description of postwar writers might be progressive.

following the war, writers showed a tendency to work on artistic or social matters rather than political themes. while postwar literature may not have been the greatest period of english literature, the themes provided excellent critics a high number of novels. such examples include anthony burgess, anthony powell and frank kermode, all of which can be placed under the progressive view.

part a. there were 250 teenagers surveyed (100% of tenagers = 250)therefore 1 % = 250/100 = 2.5 76% = 1% x 76 = 2.5 x 76 = 190 teenagers of the 250 surveyed liked burgerspart b: jane surveyed 25% (which is equal to 50 teenagers, i.e. a quarter of the teenagers surveyed is 50) to get 100% we simply get 4 quarters, i.e. multiply 50 by 4 = 200 teenagers were surveyed by jane. part c: it is impossible to give an example where a percentage is greater than 100%, since, by definition , percentage means "per 100".