On the average, more than half of the oil in a reservoir is left behind after a well has "gone dry," using primary recovery techniques.
a) true
b) false

A) True

Explanation:

As the primary recovery technique is a method of gas drive and is the first stage of petroleum and gas production and relies on due to the natural rise of pressure between the fields and bottom hole of the well. It is a less expensive than an advanced system of oil recovery and forces the oil to the surface.

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