Falling sales and rising overheads have obliged the company to review each customer's()limit.
A. credit
B. currency
C. check
D. certificate
On the end of his nose was a () of thick glasses.
A. pair
B. set
C. couple
D. suit
慢性肺源性心脏病急性期呼吸衰竭的给氧原则是
A. 持续高浓度给氧
B. 持续低浓度给氧
C. 不需给氧
D. 间断高浓度给氧
E. 间断低浓度给氧
销售合同中规定了由于特定原因买方有权退货的条款,而企业又不能确定退货的可能性,其确认收入的时点应当是 ( )
A. 发出商品时
B. 收到货款时
C. 签订合同时
D. 退货期满时