What economic factors made ghana an important trading center

Ghana was one of the most important kingdoms on the west coast of Africa. The kingdom became rich due to the gold and salt trade. It handled the traders to north and south of the kingdom, the north was full of salt mines, while the south was full of gold mines and Ghana was located in the middle of both. Due to its strong army it offered protection to the traders for a fee and set up rules like an ounce of gold for an ounce of salt. Although Ghana did not have salt or gold mines, it grew rich by handling the trade of gold and salt.

answer: the time zones used to be whatever the local authority wanted them to be. one town might have 6am whenever the sun came up and another town had 6am 10 minutes later.  

the trains had a hard time when their orders said to be at a certain point at 6am.  

6am, but who's 6am.  

the railroads got together and set the time zones more or less along the longitude lines across the country.

explanation:

a. "how old man winter was driven back” and “ormuzd and arimanes"