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问题 不定项选择

下列四个选项的图中，木块均在固定的斜面上运动，如图所示，其中图A，B，C中的斜面是光滑的，图D中的斜面是粗糙的，图A，B中的力F为木块所受的外力，方向如图中箭头所示，图A，B，D中的木块向下运动，图C中的木块向上运动。在这四幅图所示的运动过程中机械能守恒的是[ ]

A、

B、

C、

D、

答案

答案：C

单项选择题

In the United States, the first day nursery was opened in 1854. Nurseries were established in various areas during the (91) half of the 19th century; most of (92) were charitable. Both in Europe and in the U. S. , the day-nursery movement received great (93) during the First World War, when (94) of manpower caused the industrial employment of unprecedented numbers of women. In some European countries nurseries were established (95) in munitions (军火)plants, under direct government sponsorship. (96) the number of nurseries in the U.S. also rose (97) , this rise was accomplished without government aid of any kind. During the years following the First World War, (98) , Federal, State, and local governments gradually began to exercise a measure of control (99) the day nurseries by (100) them and by inspecting and regulating the conditions within the nurseries.
The (101) of the Second World War was quickly followed by an increase in the number of day nurseries in almost all countries, as women were (102) called upon to replace men in the factories. On this (103) the U. S. government immediately came to the support of the nursery schools, (104) $6,000,000 in July, 1942, for a nursery school program for the children of working mothers. Many States and local communities (105) this Federal aid. By the end of the war, in August, 1945, more than 100,000 children were being cared (106) in day-care centers receiving Federal (107) Soon afterward, the Federal government (108) cut down its expenditures for this purpose and later (109) them, causing a sharp drop in the number of nursery schools in operation. However, the expectation that most employed mothers would leave their (110) at the end of the war was only partly fulfilled.

A．by

B．after

C．of

D．for
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单项选择题

女性，35岁，胸外伤已5小时，脉搏130次/分，血压100/60mmHg，伤侧胸膜腔穿刺出血液，静置后凝固，Hb和RBC逐渐下降。此时采取的主要治疗方法是

A．胸腔穿刺

B．输血观察病情

C．胸腔闭式引流

D．开胸探查术

E．应用止血药物治疗
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