Question

By 1860 the number of miles of railroad tracks throughout the United States had risen to

Answer 1

Answer:

By 1860, 30,000 miles (49,000 km) of railroad tracks had been laid,.

By 1860, 30,000 miles (49,000 km) of railroad tracks had been laid, with 21,300 miles (34,000 km) concentrated in the northeast.