已知外界大气压为标准大气压,如图所示的托里拆利实验装置中,管内水银上方为真空,则

题型:问答题

问题:

已知外界大气压为标准大气压,如图所示的托里拆利实验装置中,管内水银上方为真空,则管内A点的压强为______,槽内B点的压强为______.

考点:液体压强的计算
题型:问答题

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

选项中有两项为多余选项。

Most people know that chocolate is made from cocoa and that the origins of chocolate can be traced back to Central and South America.  小题1: But how did chocolate go from being the food of the gods to being the food of love?

  小题2:  They established the first cocoa plantation and used the cocoa beans as the main ingredient in a dark, bitter drink that we would call “chocolate”. The Mayas believed that chocolate had mystical properties.   小题3: In fact, cocoa beans were used as a form of currency that was worth its weight in gold.

Spanish conquistador Hernando Cortez was the first European explorer to realize cocoa’s commercial possibilities.  小题4:  In 1529, Cortez returned Spain and introduced chocolate——as a drink mixed with sugar, vanilla, and cinnamon——to European society.

It caught on, especially with the nobility. As its popularity spread, people found new ways to make and use chocolate.  小题5:  Whether it is in delectable desserts or crunchy candy, people all over the world are still in love with chocolate.

A. But cocoa also had commercial value.

B. But not all the people all over the world love cocoa.

C. For centuries, the native there regarded cocoa as a gift from the gods.

D. When he arrived in the New World in 1519, he soon established his own cocoa plantation.

E. Around A. D. 600, the Mayas were the main aboriginal group in Central America.

F. These days, chocolate is enjoyed as both a tasty treat and a romantic indulgence.

G. Doctors said cocoa plays an active part in medicine.

题型:问答题

下列那种生物的发育过程中没有“蛹”这个发育阶段:             (   )

A.蝗虫  

B.蜜蜂

C.菜粉蝶

D.蚊

题型:问答题

探索规律:现有一列数,a1,a2,a3,…a97,a98,a99,a100,其中a3=9,a7=﹣7,a98=﹣1,且满足任意相邻三个数的和为同一常数,则a1+a2+a3+a4+…+a97+a98+a99+a100=(    )。

题型:问答题

作为对单位经济业务事项进行确认、计量、记录和报告的会计,设计会计标准、制定会计政策、选择会计方法,都必须遵循其内在的客观经济规律和要求。( )

题型:问答题

涕灭威原药:生产5%涕灭威颗粒剂原药含量在();生产10%、15%涕灭威颗粒剂原药含量在()。

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