小明同学用托盘天平和量筒测量石块的密度,实验步骤如下: A.用细线将石块拴好,轻

题型:问答题

问题:

小明同学用托盘天平和量筒测量石块的密度,实验步骤如下:

A.用细线将石块拴好,轻轻放入量筒内的水中,测出水和石块的总体积V

B.计算石块的密度.  C.往量筒中倒入适量的水,测出水的体积V

D.用天平称出石块的质量m.

(1)上述实验步骤的正确顺序是______.

(2)测量石块质量时,右盘有20g、5g的砝码各1个,游码的位置如图所示,天平恰好平衡,石块的质量为______g.

考点:固体密度的测量
题型:问答题

Part 4


Questions 26-45


·Read the following passage and decide which answer best fits each space.
·Forquestions26-45, markoneletterA, B, C or D on the Answer Sheet.
Both (26) and zoology are parts of a more general field of science, biology. The two are studies of (27) things, which share certain characteristics, (28) they are plants or animals. Botany deals with plants, whose organisms that can (29) their own food by the use of sunlight. Zoology on (30) hand, deals with animals, those organisms that cannot manufacture their own food and are thus dependent (31) plants for their food.
(32) plants and animals share many abilities, the extent (33) which plants can exercise some of those abilities is (34) . For example, both plants and animals need food, water, and warmth for growth, (35) plants can move to (36) those needs only by the slow extraction of their leaves and roots, while animals can move relatively (37) distances in relatively little time. When an animal is hurt with needle, the animal will (38) the part of the body (39) . This ability to draw back (40) pain or irritation, called irritability, is found only to a very limited extent in plants.
If plants (41) the same (42) as animals, animals would have had a more difficult time finding food. If animals were as limited as plants, they might (43) a means of manufacturing their own food, as plants do now. The world would be a very different place (44) it is if the characteristics of plants and animals were (45)

A.on

B.in

C.at

D.with

题型:问答题

历史唯心主义的根本缺陷在于肯定了人的意志和思想动机的作用。( )

题型:问答题

辊径为Φ290时中垫铁厚度为23.5mm,换辊时改为辊径Φ286,则中垫铁厚度为()较合适。

A、18.0mm

B、21.5mm

C、20mm

D、19.5mm

题型:问答题

根据《关于禁止商业贿赂行为的暂行规定》,下列属于商业贿赂的行为是

A.某医药公司为实现销售给予对方30%的折扣,并已如实入账

B.某制药企业为实现销售给予对方10%现金回扣,未入账

C.某制药企业为实现销售,以宣传费的形式给对方单位送了一台笔记本电脑

D.某医药公司,在宣传产品过程中给对方单位人员发送了一些笔记本

E.某医药公司为实现销售,以科研会议的形式邀请对方负责人旅游,且未如实入账

题型:问答题

美国历史学家J.布卢姆说:1787年“在费城所起草的宪法是实验时期最伟大的创造性的胜利。……战后人们最初反对君主制和贵族制政治的思想,引导着美国人民建立了一些行政首脑软弱无力、上院不起什么作用的州政府;新的宪法则建议有一个权力很大的行政首脑和同众议员权力相当的参议院。……全世界都说过,像美国规模这么大的国家,要建立共和制度是不可能的。……但是这里居然兴起了一个新型的共和国,一个虽然疆域和人口扩大十倍,但依旧对人民负责的政府,一个其人民不是作为互相对垒的公民,而是作为一个国家的平等公民联合起来的联邦。”

——《美国的历程》

为什么人们普遍认为“像美国规模这么大的国家,要建立共和制度是不可能的?”

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