From witch document does the idea of the work revolution come form?

Debatable, but the answer you're likely looking for is Karl Marx and Fredrich Engel's 1848 document on political theory, the Manifesto of the Communist Party.

Explanation:

Now known as The Communist Manifesto, the document contains Marx and Engel's analysis of communism and the class-struggle. Within, Marx writes, "The supremacy of the proletariat  will cause them to vanish still faster. United action, of the leading civilized countries at least, is one of  the first conditions for the emancipation of the proletariat." While the term "world revolution" isn't explicitly used, the passage eludes to it's underlying concepts.

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b) the confederacy had to pay all union war expenses.

a memoir is the correct answer