选择合适的句子，补全对话。（有两项是多余的）
A. What did you do yesterday?
B. Where did you go yesterday?
C. How many children were there at the party?
D. Yes, he did.
E. Why did you visit Mike?
F. No, they weren't.
G. How many children are there at the party?
A:Hello, Liu Yun. ____
B:I visited Mike.
A:____
B:Because it was his birthday yesterday.
A:Did he have a birthday party?
B:____
B:There were fifteen children at the party.
A:Were Mike's parents at home?
珠穆朗玛峰的海拔是8844.43米，西藏拉萨的海拔大约为3650米，二者的相对高度约是（ ）
