A:洗气瓶中产生的沉淀是碳酸钡
B:从Z导管出来的气体中无二氧化碳
C:洗气瓶中产生的沉淀是亚硫酸钡
D:在Z导管口有红棕色气体出现
⑴How old are you?____ A. She's fine.
⑵How is she?____ B. I'm eleven years old.
⑶How much is the fan?____ C. I have ten.
⑷How many pens do you have?____ D. It's ten yuan.
⑸How beautiful!____ E. Thank you.
4+9=____