根据对话情景，填入恰当的单词。

A: Hi, Jim! I want to do a survey about the students’ routines(作息). Can I ask you some questions?

B: Of course you can.

A: 1. __________do you usually get up?

B: At around 6:00.

A: And what time do you eat 2. __________?

B: At about 6:20. And my mother makes it for me.

A: Do you 3. __________ a bus to school?

B: No, I don’t. I often go to school on foot.

A: And what do you usually do after dinner?

B: Well, I take a walk first. Then I do my 4. __________. It takes me 2 hours. After that, I usually take

a shower, and then go to bed at around 10 o’clock.

A: What a busy day. Thanks for your interview.

工程上常用的降噪系数不采用下面哪个频率的吸声系数？（）

A、125Hz

B、250Hz

C、500Hz

D、1000Hz