多油浮选是最早使用的一种浮选法，多油浮选的用药量约占矿石重量的（）。

A、10～20%

B、5～10%

C、10%以下

D、20%以上

During a project the scope of a product purchased on a cost reimbursable contract has increased．In the contract the fee to cover the contractor's indirect costs and allow a profit is calculated as 20% of the direct costs．What is most likely to be true ？（）

A．The contractor's indirect costs will increase and the customer's payment for them will increase，to

B．The contractor's indirect costs will increase but the eLlstomer's payment for them will not increas

C．Neither the contractor's indirect costs nor the customer's payment for them will increas

D．The contractor's indirect costs will not increase but the customer's payment for them will increas