对下列二叉树
进行前序遍历的结果为______。(A) DYBEAFCZX(B) YDEBFZXCA(C) ABDYECFXZ(D) ABCDEFXYZ
参考答案:C
情景选择。
1. 别人过生日时,你应对他说: [ ]
A. How are you?
B. This is for you.
C. Happy birthday to you!
2. 你想知道别人多大时,你应该问: [ ]
A. How many?
B. How old are you?
C. How are you?
3. 送给别人东西时,你说: [ ]
A. This is for you!
B. How many gifts?
C. Thank you!
4. 当别人谢你时,你说: [ ]
A. Nice to meet you.
B. You are welcome.
C. Great!
氨制冷系统进行排污时,排污口一般设置在管道的()。
A、最高点
B、中间位置
C、最低点