从事产品认证活动的认证机构,还应当具备与从事相关产品认证活动相适应的()、()等技术能力。
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内燃机车柴油机气缸中燃气所做的指示功毫无损失地传到动轮上所得到的机车牵引力称为()牵引力。
A. 轮周
B. 车钩
C. 指示
D. 柴油机
传染病患者经氧疗()小时,pO2仍<92%,或呼吸困难、呼吸窘迫改善不明显时,宜进行机械通气治疗。
A. 2
B. 4
C. 6
D. 8
A common rail engine has only one or two high pressure pumps in operation at the same()time, and the injection into each cylinder.
A. can’t be controlled very precisely
B. can’t be controlled as flexibly as the separate pump system
C. can be controlled as flexibly as the separate pump system
D. can be controlled more precisely and flexibly
企业为提供劳务和产品而发生的各种耗费(不包括为第三方或客户垫付的款项),在会计上称为()。
A. 费用
B. 成本
C. 收入
D. 利润