What actions must the working partner (Amil) personally undertake in a Mudarabah (profit-sharing partnership)?

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The working partner must personally handle every task customarily performed by the working partner, such as spreading the cloth, folding it, showing it to the buyer, negotiating the sale, concluding the sale contract, receiving the price, inspecting it, tying and sealing the purse, and securing it in the safe, and similar matters. No separate wage is due to him for this work because his entitlement to profit serves as compensation for undertaking these actions.