制冷装置做气密试验时，为了防止冷凝器安全阀泄放制冷剂,应_______。Ⅰ、试验压力低于安全阀开启压力Ⅱ、将安全阀调紧，使其开启压力超过系统设计压力Ⅲ、将安全阀与通舷外管路脱开，阀出口端用盲板封死

多项选择题Which of the following is are key driving factor() of companies’ adopting sustainable marketing?() A、Customer demand for socially responsible products and actions. B、Companies demand sustainability initiatives from their suppliers. C、New regulations and public policies. D、Increasing cost and volatile prices of natural resources.

单项选择题电梯检修运行时，运行速度GB中有怎样的规定。（ ） A、等于0.63m s B、大于0.63m s C、小于0.63m s D、不确定