In which era did these occur: Sharecropping, Black Codes, Freedman's Bureau, Military Reconstruction Acts?

At the time of hitler's 1939 invasion of poland, the us had a policy of appeasement negotiation opposition neutrality

Which of the following descriptions is an example of the curtual diffusion

What was the main cause of the russian revolution? a. the protests against the war with poland b. the tremendous war losses of world war 1 c. the protests against the treaty of brest- litovsk d. the losses dictated by the treaty of versailles