In a fixed price contract, the cost or profit is:在固定总价合同中,费用或者利润是: A. Unknown 未知的 B. Part of the negotiation at the time of payment of each invoice在支付每张发票时谈判的一部分 C. Reflected in the invoice在发票中体现 D. Decide with others later stage of the project在项目后期与其他人一起决定