A:
B:
C:
D:
Mum:Mary. ____
Mary:It's very pretty.
Assistant: ____
Mum:Yes. ____
Assistant:It's $ 99.
Mum:Oh, that's expensive.
Assistant:Do you like that blue skirt?
Mary:Yes. ____
Mum:OK. How much is it?
Assistant:It's $ 50.
Mum: ____
A. Can I help you?
B. OK. I'll take it.
C. How do you like this dress?
D. I like blue.
E. How much is it?
用适当的介词填空
在用稀盐酸和氢氧化钡溶液进行中和反应实验时,反应过程中溶液酸碱度变化及相关数据如图所示。
(1)根据此变化曲线,你认为实验操作是将什么滴加到另一种溶液中;(2)当加入溶液的质量是a克时,滴入无色酚酞试液,溶液呈什么色,此时溶液中溶质是?(写化学式);(3) 求恰好完全反应时溶液中溶质的质量(需写出计算过程)
读20元人民币版面图案,该图案所示为我国的桂林山水,该地形景观的主要成因是( )
请你根据图中提供的信息完成下列各题: