Now create several prompt response pair based on the below text corpus:
The first model (Model I) examines a two-echelon RSC with one manufacturer and, one retailer and considers uncertainties with respect to demand, collection quantity and collection yield. The second model (Model II) studies a three-echelon RSC with one supplier, one manufacturer and, one retailer and considers random demand and collection yield with demand dependent on selling price and warranty period. Do not say the word "quantity" in the response
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