天然气的着火温度范围是多少度?
城市生态系统由()三部分构成。 ["A.自然生态系统","B.经济生态系统","C.社会生态系统","D.政治生态系统"]
Foam extinguishes a fire by(). ["shutting off the air supply","cooling the fuel to below ignition temperature","dispersing the fuel","removing the source of ignitio"]
Flames from small leaks of LFG may be extinguished by(). ["utilizing carbon dioxide or dry chemical fire extinguishers","utilizing soda and acid fire extinguishers","blowing the flames out","letting it burn itself out"]
()是指一个人在某工作生活中所经历的一系列职位、工作或职业。
赵安中先生曾挥笔写下15个大字,高瞻远瞩地点明了培养人才和依托港口“相互为用、相辅相成”的关系,指出了发展高等教育对加快宁波国际化港城建设的重要作用。请写出赵安中先生写的这句话。