电信企业细分市场的变量主要有:() ["地理变量","人口变量","心理变量","行为变量","经济变量"]
闭合导线若按逆时针编号,则观测导线()为内角。 ["A、左侧","B、右侧","C、前面","D、后面"]
《高层民用建筑设计防火规范》规定,超过800个座位的剧院、礼堂的舞台口宜设() ["防火隔墙","防火卷帘","排烟风机","防火幕或水幕分隔"]
《高层民用建筑设计防火规范》规定,高层民用建筑内超过()个座位的剧院、礼堂的舞台口宜设防火幕分隔 ["800","500","400","200"]
()和()是控制森林病虫害的治本措施
()是苗圃最主要的病害