题干

— Hello , I am Kitty .

— _________ .


A:Hello . I am Kitty

B:Hi .  Kitty

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答案(点此获取答案解析)

B

同类题1

阅读下面短文,回答相关问题。

生活中你是否遇到过这样的事情:你将苹果去皮、切块儿,等待妈妈下班回来。可是一段时间后,苹果块儿表面会生成一种褐色的物质,口感也不那么脆了......变化其实来自于苹果中存在的一种原本无色的多酚类的物质。这类物质能跟氧气结合,产生一些有色物质,这就是褐变过程。

防止苹果发生褐变过程的方法有很多。

碳酸氢钠是一种安全、价格低廉的化学物质,能够直接抑制水果病原真菌的生长,常用于水果贮藏保鲜。选择新鲜、大小均匀、无虫害无伤的苹果果实,消毒、清洗后切成12片,每片厚度约为15mm。切片立即浸泡于下表中的碳酸氢钠溶液中进行保鲜处理。每种浓度的碳酸氢钠溶液中浸泡2块苹果切片。5分钟后将苹果切片捞出、甩干,将12片苹果装在一个塑料保鲜盒中,置于4℃贮藏观察。


1

2

3

4

5

6

碳酸氢钠溶液的溶度g/L

0

0.5

2.0

5.0

10.0

15.0

pH

7.01

8.00

8.12

8.20

8.25

8.33

在贮藏3天后,取样测定其褐变度和硬度变化,记录的数据如下图1。

(注:褐变度表示苹果褐变的程度,数值越大褐变程度越高;硬度表示苹果的酥脆程度,数值越大说明越酥脆)

抗坏血酸(即维生素C)是一种抗氧化剂,也可以有效抑制苹果切分后褐变和变软。抗坏血酸在酸性环境下稳定,但是很难发挥抗氧化作用,在弱碱性环境下可以发挥很强的抗氧化作用。而苹果果实的pH一般在3.0~3.8。

取三组苹果切片,分别用10g/L某常用食品防腐剂、10g/L碳酸氢钠与10g/L抗坏血酸的混合液、对照液(蒸馏水)处理,4℃贮存并观察,记录数据如下图2:

依据文章回答下列问题。

同类题4

阅读理解

    At times my mom has been uncomfortable seeing these qualities in me. For example, when I was 12, I went to Puerto Rico all by myself to stay with my grandmother for the summer. My mom was extremely nervous about it. She kept telling me how things were different in Puerto Rico, to always put on sunscreen, not to wander away from my grandmother, and other warnings. She helped me pack and did not leave the airport until she saw my plane take off.

    Despite her worries, she let me go on my own. As I moved into my teens, she continued to give me space to grow and learn, even when it might have been difficult for her. When I reached my senior year, I decided to move away for college. Once again I found that I differed from my peers: while many of them wanted to stay close to home, I couldn't wait to be out in the world on my own. While my mom may not have been happy at the thought of my going away, she was supportive and excited for me.

    One big thing I realized during my senior year when my mom granted me more freedom was that she actually believed in me and trusted me. That meant a lot. In most time of my life, and especially when I was little, the main person I tried to impress in my schoolwork or other things was my mother. I knew she expected nothing but the best of me. Sometimes it was hard to live up to her standards; getting a single B on my report card would make me feel bad because I knew she wanted me to have all A's.

    I know that her high standards have helped me stay focused on what's important, like education, and made me who I am. I am thankful for her support and involvement in my life. Most of all I respect her. She is the strongest woman I know and that's why I have turned out so strong and independent.