农产品原料易腐坏变质的原因
参考答案：进入加工以前还没有停止生命活动或生化过程，而且这些原料也是微生物繁殖生长的营养体，因此农产
品加工原料易腐坏变质。
脑白金主要成分的结构简式如下图所示，下列对脑白金主要成分的推论正确的是
A．其官能团和营养成分与葡萄糖相同
B．其分子式为C13H15N2O
C．该物质不能与溴的四氯化碳溶液反应
D．该物质能发生水解反应并生成乙酸
The reason much refrigerated food spoils is that it ends up out of sight at the back of the shelf. So why not have round shelves that rotate Because such rotating shelves would have just the same sort of drawback, since things would fall off the shelves’ edges into the rear corners. Which of the following is presupposed in the argument against introducing rotating shelves
A．Refrigerators would not be made so that their interior space is cylindrical.
B．Refrigerators would not be made to have a window in front for easy viewing of their contents without opening the door.
C．The problem of spoilage of refrigerated food is not amenable to any solution based on design changes.
D．Refrigerators are so well designed that there are bound to be drawbacks to any design change.
E．(E) Rotating shelves would be designed to rotate only while the refrigerator door was open.
