【单选题】等量的Span -80(HLB4.3)与吐温-80(HLB15.0)混合后的HLB值是( )
【单选题】When the writer says that Jim has a full-time job at home, he means Jim______.
A.
makes shoes in his home
B.
does his extra work at night
C.
does his own car and home repairs
D.
keeps house and looks after his children
【单选题】Jim has made many friends since he ______ to China.
【简答题】国际收支平衡表包含经常项目、( )、( )和( )。
【多选题】下列关于表面活性剂的正确表述为
B.
能够显著降低溶液表面张力的物质叫作表面活性剂