The presence of dunes in the middle victoria crater on mars indicates that:

This indicates the presence of the atmosphere on Mars, which is pretty amazing. Mars has a very thin atmosphere which became like that due to the direct contact with the solar winds.  Particles from the Mars’ atmosphere were detected going in to space by Mars Express and by Mars Global Surveyor.

answer; (cognitive   dissonance);

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.