【单选题】What does the telegram say?
A.
Return immediately for his parents missed him badly.
B.
Return immediately for his aunt is expecting him.
C.
Return immediately for something unusual happened at home.
D.
Return immediately for his uncle was seriously ill at home.
【简答题】1839 年 哪个国家 ( ) 的 Goodyear , 发明了天然橡胶的硫化
【单选题】He will return____ three o'clock.
【单选题】谁发明了硫化,使橡胶工业获得突破性进展?
【判断题】1839年固特异发明了硫化技术,改善了橡胶的使用价值,橡胶制品得到了广泛应用。
【单选题】Based on the scenarios below, what is the expected return for a portfolio with the following return profile?______.