正弦波振荡器的反馈网络中，可以用（）组成，也可用（）组成。_爱下问搜题

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问题填空题

正弦波振荡器的反馈网络中，可以用（）组成，也可用（）组成。

答案

参考答案：RC元件；LC元件

单项选择题

焦亚硫酸钠和硫代硫酸钠是

A．防腐剂

B．金属螯合剂

C．抗氧剂

D．pH调节剂

E．止痛剂

完形填空

Whenever my kids have a party at school, I am the mom who always signs up to bring the juice boxes. It’s not because I’m   26  or that I don’t care if my kids have a good party. I am just not good at making homemade bread into holiday-themed shapes like other mothers.   27 , I’m happy to try, even though it’ll   28  me a long time to do it.
People say that housewives should have the   29  to make delicious meals, keep their houses clean, and   30  every minute of their child’s life. Their words used to   31  me a lot. I felt that I should also be able to do those things as a housewife. So   32  I couldn’t make the turkey-shaped cookies, I   33  feeling like a failure as a mom.
After many   34  attempts at baking, and many afternoons spent crying over my inabilities as a mother, I finally accepted the   35  that my lot(命运) in life is to be the juice box mom. I worked hard to be the   36  one in the elementary school. And after one of my daughter’s class parties, it   37 . Her teacher stopped me as I was leaving and said,＂Thank you so much for always bringing   38  drinks. Sometimes parents forget that other children will also   39  class parties, and they end up being left out because we don’t have enough   40  for everyone.＂
I just accepted her appreciation, rather than telling her that I brought extra drinks because I could   41  remember how many kids were in the class. But her   42  taught me an important lesson: I’m not a failure as a mom.
Not everyone is cut out to be a(n)   43  mom. I believe it’s okay to be the juice box mom. I may not bake cookies and decorate them beautifully, but I   44  something to drink. And I think that’s just as   45 .

C．insisted on

A．contribution

B．appreciation

C．Congratulation

D．comprehension

C．interesting