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问题 填空题

水的密度是______Kg/m3，它表示______．水结成冰密度变______（填“大”或“小”）

答案

（1）密度的定义是单位体积某种物质的质量，水的密度是1.0×103kg/m3，它表示体积为1m3的水质量是1000kg；

（2）质量是物质的属性，一杯水结成冰，所含物质多少没变，质量m不变；但水结冰后体积V变大，

根据公式ρ=

m
V
，当m一定时，体积变大，密度变小，即冰的密度小于水的密度；

故答案为：1.0×103；体积为1m3的水质量是1000kg；小．

单项选择题 A1/A2型题

常用于检测高压蒸汽灭菌器灭菌效果的商品菌片是 （）

A.枯草芽孢杆菌黑色变种（ATCC9372）

B.大肠埃希菌（ACTT25922）

C.嗜热脂肪芽孢杆菌（ATCC7953）

D.铜绿假单胞菌（ATCC27853）

E.金黄色葡萄球菌（ATCC25923）
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单项选择题

The Japanese Macaca monkey has been studied in the wild for over 50 years. In 1952, on one small Japanese island, scientists dropped some (21) in the dirt for the monkeys. The monkeys liked their taste, but they found the dirt (22) .
One clever 18-month-old monkey found she could (23) the problem by washing the sweet potatoes in a nearby river. She taught this to her mother. Her (24) also learned this new way and they taught their mothers too.
All the younger monkeys (25) learned to wash the dirty sweet potatoes to make them (26) to eat. But many old monkeys found it very hard to learn this and still ate the (27) sweet potatoes.
Then something very strange (28) In the autumn of 1958, scientists found that the monkeys on other nearby (29) began washing their sweet potatoes too. Scientists still don’t fully understand how this knowledge was (30) from one island to another.

Ⅱ. 完形填空

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阅读下面短文，掌握其大意，然后再各题所给的四个选项(A、B、C和D)中选出一个最佳选项。

A．children

B．brothers

C．sisters

D．friends
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