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问题 判断题

属于国家进口许可证管理商品的进料加工项下进口料件一律免领进口许可证。( )

答案

参考答案：错

解析： 除易制毒化学品、监控化学品、消耗臭氧层物质、原油、成品油等个别规定商品外，进口料件均可以在报关进口时免予交验进口许可证件；出口成品属于国家规定应交验出口许可证的，在出口报关时必须交验出口许可证。

实验题

小刚用加热氯酸钾的方法制取氧气。实验装置示意图如下：

（1）写出下列序号仪器的名称： ①____________，②____________，③____________。

（2）实验室用氯酸钾制取氧气反应的文字表达式：____________。

（3）实验室制取氧气的主要操作步骤有：①从水槽中取出导管；②检验装置的气密性；③停止加热；④收集气体；⑤加热；⑥加入药品，请写出正确的操作顺序____________（填序号）。

（4）检验装置气密性的操作如下：先将导管伸入液面下，用手紧握试管，观察到________________________，松开手后，导管口有液面上升。

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单项选择题

Up until a few decades ago, our visions of the future were largely—though by no means uniformly— glowingly positive. Science and technology would cure all the ills of humanity, leading to lives of fulfillment and opportunity for all.
Now utopia has grown unfashionable, as we have gained a deeper appreciation of the range of threats facing us, from asteroid strike to epidemic flu to climate change. You might even be tempted to assume that humanity has little future to look forward to.
But such gloominess is misplaced. The fossil record shows that many species have endured for millions of years—so why shouldn’t we Take a broader look at our species’ place in the universe, and it becomes clear that we have an excellent chance of surviving for tens, if not hundreds, of thousands of years. Look up Homo sapiens in the "Red List" of threatened species of the International Union for the Conversation of Nature (IUCN) and you will read: "Listed as Least Concern as the species is very widely distributed, adaptable, currently increasing, and there are no major threats resulting in an overall population decline."
So what does our deep future hold A growing number of researchers and organizations are now thinking seriously about that question. For example, the Long Now Foundation has its flagship project a mechanical clock that is designed to still be marking time thousands of years hence.
Perhaps willfully, it may be easier to think about such lengthy timescales than about the more immediate future. The potential evolution of today’s technology, and its social consequences, is dazzlingly complicated, and it’s perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage. That’s one reason why we have launched Arc, a new publication dedicated to the near future.
But take a longer view and there is a surprising amount that we can say with considerable assurance. As so often, the past holds the key to the future: we have now identified enough of the long-term patterns shaping the history of the planet, and our species, to make evidence-based forecasts about the situations in which our descendants will find themselves.
This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad. To be sure, the future is not all rosy. But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans, and to improve the lot of those to come.

Our vision of the future used to be inspired by

A. our desire for lives of fulfillment.
B. our faith in science and technology.
C. our awareness of potential risks.
D. our belief in equal opportunity.
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