According to Mark Kurlansky, why did people use salt?

All this trade led to the founding of cities. City governments became necessary, as well as men trained to be put in charge of keeping accounts, of maintaining law and order, of ensuring the safety of citizens.

hope this helped

the effect of the ming leaders banning ships with more than two masts was that there was no further construction of ships masts, because there was a surplus. ming emperors disallowed foreign exploration