| Sound moves from its source to the ear
by wave like fluctuations in air pressure, something like the peaks and troughs
or the lowest point of ocean waves. One way to keep from hearing sound is to use
ear plugs. Another way is to cancel out the sound with anti-sound. Using a noise maker controlled by a microprocessor, engineers have produced sound waves that are half a wavelength out of phase with those of the noise to be quieted--each peak is matched to a trough, and vice versa. Once the researchers have recorded the offending sound, a microproce A. the nature of fog B. a way to improve alarm systems C. other causes of fatigue D. other uses of the microprocessor [单项选择]The road from Mildum to Merbein, in north-west Victoria, is a sad sight. Many of its farms are covered with wine grapes, dying on the vines. Farmers planted the vines hoping to cash in on the seemingly endless boom in Australian wine. But in 2007 the boom turned to bust, forcing many farmers to walk away from grapes and land they cannot sell.
Over the past 15 years Australia’s wine industry has been one of its great success stories. Export revenues last year reached A$3 billion ($2.4 billion), four times the figure from 1997. Britain, America and Canada, among the most competitive markets for wine, are Australia’s three biggest customers. But the suffering in places like Mildum and nearby Renmark in South Australia is a sign that the industry fell victim to its own success. Flushed with a growing demand for Australian wines, a grape shortage, and soaring grape prices, growers rushed to plant more vines in the late 1990s. In 1998 they put in a record 16,000 new hectares, doubl A. turned to bust since 15 years ago. B. revived in the year 2007. C. had virtually no competitors. D. boomed over the past 15 years. [多选题]根据《建筑地基基础工程施工质量验收标准》(GB50202-2018),膨胀土地区散水质量检验标准的一般项目包括:( )
A.石灰粒径 B.垫层厚度 C.散水坡度 D.散水宽度 E.面层厚度 [多项选择]各级国库加强国库会计管理的目的是（）。
A. 加强国库会计工作管理 B. 建立健全内控机制 C. 确保国库资金安全 D. 提高国库会计工作水平 [填空题]硫化氢的工业卫生允许浓度是≤10mg/m3 ，用（） 的滤毒罐防护。
[判断题]焊接出现质量问题，应从人、机械、材料、方法和环境5个方面分析原因 。
A.正确 B.错误 [简答题]结合实际谈谈，为什么说企业的培训需求是一个永恒的话题？
[单项选择]The lighting in the art gallery was very simple, but very {{U}}effective{{/U}}.
A. impressive B. capable C. useful D. comfortable [判断题]凡发生有影响的火灾.抢险救援行动时，由各级指挥中心整理《值班信息快报》。（）
A.正确 B.错误 我来回答: 提交
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