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问题 选择题

下面是五位同学在使用显微镜观察标本时的操作，其中正确的是

甲：将反光镜对着太阳光以使视野内达到最大亮度

乙：观察标本时，两眼张开，左眼观察，右手画图

丙：使用低倍物镜看不到细胞，于是换高倍物镜期望能观察到细胞

丁：使用低倍物镜已看到有些模糊的细胞，于是试着调细准焦螺旋

戊：根据自己观察的物像绘图以后，发现不够美观，又进行了修改

A．甲、乙、丙

B．乙、丁、戊

C．乙、丁

D．乙、戊

答案

答案：C

题目分析：使用显微镜对光时，要根据所观察的标本的情况进行对光，光线有时不能太强，也不能太暗，甲的说法不符合题意；观察标本时，两眼都要张开，左眼观察，右手画图，乙的说法符合题意；使用低倍显微镜先找到图像的视野，才可以换成高倍镜观察，如果在低倍镜没有找到视野，即使换成高倍镜也不能观察到细胞，丙的说法不符合题意；使用低倍物镜已看到有些模糊的细胞，于是试着调细准焦螺旋，使图像更清晰，丁的说法符合题意；绘制图像时要真不真实性，根据自己观察的物像绘图以后，发现不够美观，不能进行不符合事实的进行修改，戊的说法不符合题意，故选项C符合题意。

填空题

找出下面各组数的最大公因数。   

（1）4和15   （4，15）=（   ）  

（2）16和7   （16，7）=（   ）   

（3）11和13 （11，13）=（   ）
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单项选择题

Questions 96-100 are based on the following passage.
In most aspects of medieval life, the closed corporation prevailed. But compared to modern life, the medieval urban family was a very open unit: for it included, as part of the normal household, not only relatives by blood but a group of industrial workers as well as domestics whose relation was that of secondary members of family. This held for all classes, for young men from the upper classes got their knowledge of the world by serving as waiting men in a noble family: what they observed and overheard at mealtime was part of their education. Apprentices lived as members of the master craftsman’s family. If marriage was perhaps deferred longer for men than today, the advantages of home life were not entirely lacking, even for the bachelor.
The workshop was a family; likewise the merchant’s counting house. The members ate together at the same table, worked in the same rooms, slept in the same or common hall, converted at night into dormitories, joined in the family prayers, participated in the common amusements.
The intimate unity of domesticity and labour dictated the major arrangement within the medieval dwelling-house itself. Houses were usually built in continuous rows around the perimeter of their gardens. Freestanding houses, unduly exposed to the elements, wasteful of the land on each side, harder to heat, were relatively scarce: even farmhouses would be part of a solid block that included the stables, barns and granaries. The materials for the houses came out of the local soil, and they varied with the region. Houses in the continuous row forming the closed perimeter of a block, with guarded access on the ground floor, served as a domestic wall: a genuine protection against felonious entry in troubled times.
The earliest houses would have small window openings, with shutters to keep out the weather; then later, permanent windows of oiled cloth, paper and eventually glass. In the fifteenth century, glass, hitherto so costly it was used only for public buildings, became more frequent, at first only in the upper part of the window. A typical sixteenth-century window would have been divided into three panels: the uppermost panel, fixed, would be of diamond-parted glass; the next two panels would have shutters that opened inwards; thus the amount of exposure to sunlight and air could be controlled, yet on inclement days, both sets of shutters could be closed, without altogether shutting out our light. On any consideration of hygiene and ventilation this type of window was superior to the all-glass window that succeeded it, since glass excludes the bactericidal ultra-violet rays.

The urban family unit described in the passage ______.

A．consisted of people related by blood

B．was made up of workers, servants and family members

C．excluded domestics and craftsmen

D．was composed of members of the same social class
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