Where were most railroads prior to the Civil War? South, North or West

south       can i have brainlist?

Explanation:

The Civil War is the first war in which railroads were a major factor. The 1850s had seen enormous growth in the railroad industry so that by 1861, 22,000 miles of track had been laid in the Northern states and 9,500 miles in the South.

nuclear fission produces the atomic bomb, a weapon of mass destruction that uses power released by the splitting of atomic nuclei the fighting in iwo jima and okinawa affected the allies' pacific strategy because truman decided to drop the atomic bomb on mainland japan.

what are the choices?