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当居室前后的窗子打开时，“过堂风”会把侧面墙上的衣柜门吹开，这是因为柜外的空气流速___\_，衣柜内的空气压强______衣柜外的空气压强（填“大于”、“小于”或“等于”）．
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当居室前后窗子打开时，“过堂风”会把侧面墙上的衣柜门吹开，这是因为衣柜外___\_衣柜内______．
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用吸管吸饮料时，在___\_的作用下使饮料上升到嘴里；居室前后两面的窗子打开时，“过堂风”会把居室侧面的衣柜的门吹开，这主要是由于衣柜门外表面的空气流速较大，压强______（选填“较大”或“较小”）造成的．
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Firefighters ane often asked to speak to school and community groups about the importance of fine safety, particularly fire prevention and detection. Bccause smoke detectors reduce the risk of dying in a fire by half. firefighters often provide audiences with information on how to install these protectivc devices in their homes.
Specifically, they tell them these things: A smoke detector should be placcd on each floor of a home. While sleeping, people are in particular danger of an emergent fire、 and there must he a dctcctor outside each sleeping area. A good site for a detecior would he a hallway that runs between living spaces and bedrooms.
Because of the dead-air space that might be missed by hot air bouncing around above a fire, smoke detcctors should be installed either on the ceiling at least four inches from the nearest wall, or high on a wall at least four, but no further than twelve, inches from the ceiling.
Deteccors should not be mounted near windows, entrances, or other places where drafts （过堂风) might direct the smoke away from the unit. Nor should they be placed in kitchens and garages, where cooking and gas fumes are likely to cause false alarms.
One responsibility of a firefighter is to______.
A．install smoke detectors in residents homes
B．check if smoke detectors are properly installed
C．develop fire safety programs for schools
D．speak to residents about how to prevent fires -
能够说明流体压强与流速的关系的现象是（）
A．高度越高，大气压强越小
B．当居室前后两面的窗子都打开时，“过堂风”会把居室侧面摆放的衣柜的门吹开
C．用吸管吸饮料时，饮料会上升到嘴里
D．塑料挂钩的吸盘贴在光滑的墙面上，能承受一定的拉力而不脱落