下列关于防排烟设施要求说法正确的有()
A. 防烟卷帘要求气密性好,不般不超过5m,设置在走道时落下高度距地1.8m以上;
B. 当烟气温度超过280℃时,排烟防火阀自动开启;
C. 固定式挡烟板和挡烟梁要求突出顶棚≥0.5m;
D. 防火卷帘和活动式挡烟板通常与火灾自动报警探测器联动
建筑防排烟方式有哪些()
A. 自然排烟
B. 机械排烟
C. 材料不燃化防烟
D. 机械加压防烟
【单选题】To ensure a successful business trip, use _________ to stay in control of every detail.
A. a secured international phone plan
B. a choice of best accommodations
C. a detailed plan of action
D. the company’s travel policy.
【单选题】During a business trip, it’s important to _________ and keep all of your receipts.
A. use a company card to cover travel expenses
B. track your purchases
C. pay for item yourself
D. create a backup plan
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