What was the main cause of the Civil War according to historians?

Which of the following farming methods the inca farm the hillsides a) slash- and- burn b) crop rotation c) irrigation canalsd) dam construction

By choosing to resupply fort sumter, abraham lincoln risked a. abandonment of the fort by union soldiers. b. abandonment of the fort by confederate soldiers. c. the appearance of giving in to confederate secession. d. armed conflict with southern soldiers.

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