What is the total amount of money owed by the government?
a. the national investment
b. the national debt
c. the national deficit
d. the national balance

i think it is the third one.

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.

answer; regard the action of other people negatively;

answer; silence;