この商品は人気があるから、十日ぐらいで売り切れるはずだ
Can someone explain what the で in this sentence means? As far as I know で has these 3 meanings: 1 - (連用形) of the assertive auxiliary (断定の助動詞), or "copula", だ/です 2 - 主体を表す。This で is used to indicate the agent of the action. 3 - で as marking "how". It specifies how something happens.