Need help with proofreading

Hello!
I am doing a proofreading at the moment and need help with a few issues, as I have been working since 8 o'clock today and my mind is not sure of anything anymore.


@page { size: 21cm 29.7cm; margin: 2cm } P { margin-bottom: 0.21cm }
"Since 1900, United States changed between what historians call "public actions and private interests."" - I feel the comma is not needed here. What do you think?


@page { size: 21cm 29.7cm; margin: 2cm } P { margin-bottom: 0.21cm }
"In another time, they become disillusioned with the social experiments and focus on themselves." - never heard of such a phrase. I would remove 'at' leaving 'another time' only. What's your idea?


@page { size: 21cm 29.7cm; margin: 2cm } P { margin-bottom: 0.21cm }
"At the beginning of the Great Depression, the pendulum swung again, and Roosevelt's New Deal and Truman's Fair Deal focuses on government actions to alleviate the social misery." - Any ideas about this one? I would remove all the commas and changes the word 'focuses' into 'focus'.


@page { size: 21cm 29.7cm; margin: 2cm } P { margin-bottom: 0.21cm }
"Conservatism returned during 1950 under Eisenhower, to be followed by a shift in the direction of liberalism in the “new frontier” of Kennedy and Johnson's “Great Society”." - Wouldn't you add 's' to 1950 and have 1950s - this is what I feel with the word during. The New Frontier or New Frontier? I would also remove the quoting marks and write it in capital letters. The same with Great Society - no capitals.



"It reached a climax in the selection of Ronald Regan in 1990." - What about this? It 'reached a climax' or it 'reached climax' is enough here? 'Selection' should be 'election' obviously, but what about the phrase 'in the election'? Shouldn't it be 'after the election'?

Thabk you so much for all your answers and help.

All the best,

Finka