题干

学完“二氧化碳性质的探究”后,小明同学觉得按照实验(图①)不能完全说明是什么物质使紫色石蕊溶液变红色,他和小娜同学进行了如下实验探究:

【猜想与假设】

猜想一:水使紫色石蕊溶液变红

猜想二:二氧化碳使紫色石蕊溶液变红猜想三:二氧化碳与水反应生成的新物质使紫色石蕊溶液变红

【查阅资料与实验准备】

将纸条浸泡在紫色石蕊溶液中,晾干后可制得紫色石蕊试纸.自制的紫色石蕊试纸遇酸变红色,遇碱溶液变蓝色.

【设计与实验】

小明同学设立了实验装置如图②.

图中a、b、c为紫色石蕊试纸,缠绕在小试管上,其中a和c用水湿润。

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       Q:My neighbor's back garden is an overgrown jungle for a few months and I believe I've got rats under my shed as a result. I have been troubled by such a bad scene for a long time.Can I make my neighbor manage her back garden?

       A:Firstly, you will need to contact a pest control company to deal with the rat problem, which could be a danger to you and your family. The pest control company will produce a report detailing the issue and give an opinion as to whether your neighbor's overgrown garden has caused the rats to run in all directions.

      If that is the case, then you should get in contact with your neighbor in an attempt to resolve the issue. You should discuss your concerns with all your heart with your neighbor and advise her of the situation and of the findings of the pest control company.

     You do not advise whether the house is rented out or perhaps your neighbor is elderly without the ability to deal with the problem personally. If your neighbor is uncooperative, then I would advise you undertake the following action.

     Get in contact with your local authority or the Department of Environment, Community and Local Government and report your concerns, particularly the pest issue immediately.You could also contact the HSE, more especially if children use the garden and are likely to come in contact with rat droppings etc, which can be dangerous to them. If the above is not successful, you should inform your lawyer and take advice. You should also document your conversations with your neighbor.

     If your house is for sale, ask your agent to prepare a report outlining the effect of the next door garden on value, but also outlining the effect on marketability and the negative impact on viewings.

Notes

①uncooperative adj.不愿合作的,不愿配合的 ②authority n.权力,职权,官方,当局 ③marketability n.可销售性