What is the required levy on a merchant from a people at war (Harbi)?

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The *Ushr* (one-tenth) is to be taken from every merchant belonging to the people at war (Harbi). This is an obligation applied equally to all, regardless of whether they are male or female, young or old, because this levy is specific to trade assets used within the Islamic domain, and the general prophetic narrations concerning it contain no exception for women.