How does a production possibility chart illustrate how efficient an economy is?

The production possibilities frontier is the line that shows the maximum possible output for that economy. Efficiency means using resources in such a way as to maximize the production of goods and services. An economy producing output levels on the production possibilities frontier is operating efficiently.

answer; i believe the correct answer is (general);

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.