换热器小浮头漏，可将小浮头焊死。

“我和你们都要以这样一种精神来面对共同的困难。感谢上帝，这些困难都只是物质方面的。价值贬缩到难以想象的程度：赋税增加了；我们的支付能力降低了：各级政府都遇到严重的收入减少；在贸易交往中交换手段也被冻结了；工业企业尽成枯枝残叶；农场主的产品找不到市场；千万个家庭的多年积蓄毁于一旦。”     ——罗斯福首次就职演说（1933年3月4日）

请回答：

（1）罗斯福是在怎样的历史背景下发表这个演说的？

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（2）面对这样的形势，罗斯福采取了什么对策？这一对策的核心措施是什么？有何特点？

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（3）这一对策的实施有哪些历史作用？

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下列说法中正确的是（　　）

A．等物质的量浓度NaCl和CH₃COONa溶液等体积混合，

c（Cl^-）＞c（Na⁺）＞c（CH₃COO^-）＞c（OH^-）＞c（H⁺）

B．25℃时，若10mL盐酸（pHa）与100mLBa（OH）₂溶液（pHb）混合后恰好中和，则pHa+pHb=13

C．等物质的量浓度的硫酸与醋酸钠溶液等体积混合，c（SO₄^2-）+c（OH^-）=c（H⁺）+c（CH₃COOH）

D．向氨水中加水稀释，

当载气流速远小于最佳流速时，为了提高柱效，合适的载气为（）。

A、摩尔质量大的气体

B、摩尔质量小的气体

C、中等摩尔质量的气体

D、任何气体均可

Advertisers tend to think big and perhaps this is why they’re always coming in for criticism. Their critics seem to resent them because they have a flair for self-promotion and because they have so much money to threw around. "It’s iniquitous," they say, "that this entirely unproductive industry (if we can call it that) should absorb millions of pounds each year. It only goes to show how much profit the big companies arc making. Why don’t they stop advertising and reduce the price of their goods After all, it’s the consumer who pays."
The poor old consumer. He would have to pay a great deal more if advertising didn’t create mass markets for products. It is just because of the heavy advertising that consumer goods are so cheap. But we get the wrong idea if we think the only purpose of advertising is to sell goods. Another equally important function is to inform. A great deal of the knowledge we have about household goods derives large from the advertisements we read. Advertisements introduce us to new products or remind us of the existence of ones we already know about. Supposing you wanted to buy a washing-machine, it is more than likely you would obtain details regarding performance, price, etc. from an advertisement.
Lots of people pretend that they never read advertisements, but this claim may be seriously doubted. It is hardly possible not to read advertisements these days. And what fun they often are, too] Just think what a railway station or a newspaper would be like without advertisements. Would you enjoy gazing at a blank wall or reading railway by-laws while waiting for a train Would you like to read only closely-printed columns of news in your daily paper A cheerful, witty advertisement makes such a difference to a drab wall or a newspaper full of the daily ration of calamities.
We must not forget, either, that advertising makes a positive contribution to our pockets. Newspapers, commercial radio and television companies could not subsist without this source of revenue. The fact that we pay so little for our daily paper, or can enjoy so many broadcast programs is due entirely to the money spent by advertisers. Just think what a newspaper would cost if we had to pay its full price !
Another thing we shouldn’t forget is the "little ads", which are in virtually every newspaper and magazine. What a tremendously useful service they perform for the community ! Just about anything can be accomplished through these columns. For example, you can find a job, buy or sell a house, announce a birth, marriage or death in what used to be called the "hatch, match and dispatch" columns; but by far the most fascinating section is the personal or "agony" column. No other item in a newspaper provides such entertaining reading or offers such a deep insight into human nature. It’s the best advertisement for advertising there is!

The writer seems to think that critics’ judgment on the role of advertising is______

A. reasonable.
B. unfair.
C. superficial.
D. foolish.

无终端盒成端的具体操作方法是什么？