How was the institution of slavery defended States’ Right doctrine?

According to jean-jaquees rousseau, individuals participating in a social contact agree to be ruled by

Which answer best describes an advantage of shipping goods by canal? most towns would rather have canals than noisy railroads. goods could travel very fast downstream in the canal system. travelling by boat is a much more relaxing way to transport goods. heavy loads of goods could travel by boat more easily than if pulled by horses.

During industrialization which led to an exploration of new economic theories