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Practically every modern building is supplied with stairways of some kind. A stairway is designed to provide a means of access between different floor levels of a building. Nowadays stairways are produced of various construction materials but the most popular among them are timber and reinforced concrete. Of them timber may be used for domestic stairs of all kinds because of its economical availability. As to reinforced concrete it is popular because of its durable qualities, great resistivity to decay and great resistance to fire.
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Why are stairways produced of reinforced concrete so popular?
Because of access between different floor levels of a building.
Because of its economical availability.
Because of various construction materials.
Because of its durable qualities, great resistivity to decay and great resistance to fire.