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Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance is extracted from natural rose oil at a cost of thousands of dollars a pound; an identical synthetic substance can be made for 1% of this cost. Since the early twentieth century, success in reproducing these substances has created a new industry that today produces hundreds of artificial flavors and fragrances. Some natural fragrances are easily synthesized; these include vanillin, the aromatic ingredient in vanilla, and benzaldehyde, the aromatic ingredient in wild cherries. Other fragrances, however, have dozens, even hundreds of components. Only recently has it been possible to separate and identify these ingredients by the use of gas chromatography and spectroscopy. Once the chemical identity is known, it is often possible to A. How to Synthesize Fragrances B. Synthetic Substances Are Easy to Make C. Natural Flavorings and Fragrances D. Synthetic Flavors and Fragrances [单项选择]（）属于正确的性动机。
A. 性爱、情爱相互依存并融为一体 B. 性角色、性身份融为一体 C. 感性、理性相互依存并融为一体 D. 性医学、性道德融为一体 [多选题]各单位应按照______，_______，_______的策略，开展修复工作。修复实施中，应密切关注与修复工作关联信息系统的运行情况。
A.先测试后生产 B.先办公再生产 C.先外围后核心 D.先备机后主机 [填空题]建立健全档案利用制度,根据档案密级、内容和利用方式等, 执行不同的（ ）。
[判断题]《中国铁路上海局集团有限公司乘意险实施细则》(上铁客〔2020〕178号)规定，持通票旅客途中通票有效期终了，则原所购的乘意险自通票有效期终了时自动解除。
A.正确 B.错误 [填空题]在试验和推广新技术、新工艺、新设备、新材料的同时,应制定相应的安全措施,经本单位( )批准后执行。
[单选题]1墙面等处的竖向洞口，凡落地的洞口应加装固定式的防护门，门栅格的间距不应大于( ) 。
A.13cm B.14cm C.15cm D.16cm [单项选择]OMP板与电源模块的通信采用（）。
A. RS485电缆 B. HW线 C. 交叉网线 D. 直连网线 [判断题]由于埋弧焊属于机械化操作，对焊工的个人防护用品没有什么要求。
[填空题]The launching of Shenzhou VI spacecraft was__________________________(具有历史意义的事件).
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