In what way was the Arabian peninsula similar to Constantinople ?

On the basis of geography.

Explanation:

The Arabian peninsula is similar to Constantinople on the basis of its geography because both the Arabian peninsula and Constantinople have surrounded by water at three sides whereas connected with the land at one side. The Arabian peninsula has surrounded by water on the east west and south but connected with Iraq from the north side while on the other hand, the Constantinople is surrounded by water at north and south side and connected with the land at the east and west side.

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.