What is single-member executive system?

A single-member district or single-member constituency is an electoral district that returns one officeholder to a body with multiple members such as a legislature. This is also sometimes called single-winner voting or winner takes all.

Explanation:

Hope it helps

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.