Ad vercundiam occurs when the ad attempts to persuade by presenting only two choices

the factors that the economies of the muslim empires prosper were:

1- land trade routes-located between three continents  

2- sea trade routes

trade contributed to the spread of muslim empires, and with that islamic culture led to a growing feeling of internationalism resulted in the transfer of technology, science, and other cultural forms.

could you go a bit more in depth with you question? it's quite hard to understand. as soon as you do that i will be glad to : )