What is Periplus of the Erythraean Sea

The Periplus of the Erythraean Sea, also known by its Latin name as the Periplus Maris Erythraei, is a Greco-Roman periplus written in Koine Greek that describes navigation and trading opportunities

1 a

2 c

3 c

4 b

5 a

hope this

answer; i believe the correct answer is (favorable balance);