我国制定的卫生标准属于（）。 A.卫生行业标准 B.国家强制性标准 C.国家推荐性标

在诸多交流调整系统中，以变频调速的性能最好、调整范围大、静态稳定性好、运行效率高。有关变频调速的工作原理分述如下，描述中哪一项是不正确的()

A．改变交流电动机的供电频率，可以改变其同步转速，实现调速运行

B．对于工业中大量使用的异步电动机，进行调速控制时，希望将电动机的主磁通保持为额定值不变，并能按要求进行控制

C．保持电动机的气隙主磁通不变的目的，是为了保持电动机的负载能力；而按要求对主磁通进行控制则是为了进行恒功率控制

D．为进行恒功率控制，当电动机由额定频率向上增大时，其主磁通应随之向上增大

税款不随商品价格增减而变动的是（）。

A.从价税

B.从量税

C.直接税

D.间接税

A lazy Susan is an addition to a table that is designed to assist in moving food from one person to another while dining. This is achieved through the use of a turntable (转盘), which usually moves the food in a circle when it is pushed by those at the table. In this way, the food never has to be picked up and passed around the table. Instead, it remains in place on the lazy Susan.

A lazy Susan may also be a part of a kitchen cabinet (橱柜). In this sense, the lazy Susan is a type of shelving unit within the cabinet that is able to turn around its axis(轴心) . One may turn the lazy Susan in order to find certain goods in storage. From the outside, a lazy Susan appears to be two cabinets that are located at a right angle (直角) to each another. When one of these cabinets is pushed, however, both doors move and the lazy Susan is revealed inside.

It is believed that Thomas Jefferson invented the lazy Susan in the 18th century, though it was called “dumbwaiter” at that time. It is said that Jefferson invented the lazy Susan because his daughter complained she was always served last at table and, as a result, never found herself full when leaving the table. Others believe that Thomas Edison was the inventor, as he is believed to have invented the turntable for his phonograph (留声机). The turntable may have developed into the lazy Susan later.

Regardless of who invented it, it wasn’t until 1917 that the term “lazy Susan” was used in an advertisement for the invention. In Britain, however, the term “dumbwaiter” is still used rather than “lazy Susan”. The reason for the naming of it is still a mystery. One theory is that it was named after either Jefferson’s or Edison’s daughter, both of whom were named Susan.

小题1:What is a “lazy Susan”?

A．A waitress

B．A convenient tool

C．A table

D．A cabinet小题2:According to those who believed Thomas Jefferson invented the lazy Susan, _______.

A．his daughter was very lazy

B．the lazy Susan didn’t exist until the 18th century

C．Thomas Edison was his friend

D．Thomas Edison didn’t invent the phonograph小题3:We can learn from the last paragraph that ___________.

A．the lazy Susan can work by itself

B．the lazy Susan was named after Thomas Edison’s daughter

C．how the lazy Susan got its name remains unknown

D．the lazy Susan was invented in Britain小题4: The writer wrote the passage mainly to _________.

A．discuss how the lazy Susan was named

B．teach us how to make a lazy Susan

C．introduce Thomas Edison’s inventions

D．tell us what a lazy Susan is and its origin

HSE管理体系遵循PDCA循环模式中“D”指的是（）。

A、处理阶段

B、检查阶段

C、计划阶段

D、执行阶段

下述不属于局部E－R图集成为全局E－R图时可能存在的冲突是( )。

A．模型冲突

B．结构冲突

C．属性冲突

D．命名冲突