已知集合M={1,2,3},N={1,2,3,4},定义函数f:M→N且点A(1

题型:填空题

问题:

已知集合M={1,2,3},N={1,2,3,4},定义函数f:M→N且点A(1,f(1)),B(2,f(2)),C(3,f(3));若△ABC 的内切圆圆心为D,且
.
DA
+
.
DC
.
DB
(λ∈R)
,则下列结论正确的有______.(填上你认为正确的命题的序号)
①△ABC必是等腰三角形; 
②△ABC必是直角三角形;
③满足条件的实数λ有3个; 
④满足条件的函数有l2个.
考点:平面向量的应用
题型:填空题

结核性渗出性胸膜炎()

A.以阻塞性通气功能障碍为主

B.以限制性通气功能障碍为主

C.混合性通气功能障碍

D.以弥散障碍为主

E.以呼吸中枢功能障碍为主

题型:填空题

阅读下面语段,按要求回答问题:

诺贝尔发明烈性炸药的出发点是造福人类,但在实际运用中,它也会成为杀人武器;电脑已成为人们生活中不可或缺的工具,但电脑病毒就如幽灵一般时刻困扰着人类;医用克隆技术可以保障人的健康,但生殖克隆技术却给人带来了伦理上的挑战。

  上述事实支持的要点是()

A.科技给人类什么取决于如何应用科技

B.必须规范技术开发者和使用者的行为

C.科技进步同时带给人类威胁与困扰

D.科技进步带给人类全新的挑战与问题

题型:填空题

赵某,妊娠38周,下肢水肿1周,头痛半天,无恶心、呕吐,胎心率132次/min,血压21.3/14.6kPa (160/110mmHg),下肢水肿(++),尿蛋白(++),应考虑

A.妊娠合并肝炎
B.妊娠合并慢性肾炎
C.妊娠水肿
D.中度妊高征
E.先兆子痫

题型:填空题

Du Bois was a sociological and educational pioneer who challenged the established system of education that tended to restrict rather than to advance the progress of black Americans. He challenged what is called the “Tuskegee machine” of Booker T. Washington, the leading educational spokesperson of the blacks in the U. S. . As a sociologist and historian, Du Bois called for a more determined and activist leadership than Washington provided.

Unlike Washington, whose roots were in southern black agriculture, Du Bois’s career spanned both sides of the Mason-Dixon Line. He was a native of Massachusetts, received his undergraduate education from Fisk University in Nashville, did his graduate study at Harvard University, and directed the Atlanta University Studies of Black American Life in the South. Du Bois approached the problem of racial relations in the United States from two dimensions: as a scholarly researcher and as an activist for civil rights. Among his works was the famous empirical sociological study, The Philadelphia Negro: A Social Study, in which he examined that city’s black population and made recommendations for the school system. Du Bois’s Philadelphia study was the pioneer work on urban blacks in America.

Du Bois had a long and active career as a leader in the civil rights movement. He helped to organize the Niagara Movement in 1905, which led to the National Association for the Advancement of Colored People (NAACP), established in 1909. From 1910 until 1934, Du Bois edited The Crisis, the major journal of the NAACP. In terms of its educational policy, the NAACP position was that all American children and youth should have genuine equality of educational opportunity. This policy, which Du Bois helped to formulate, stressed the following themes: (1) public schooling should be free and compulsory for all American children; (2) secondary schooling should be provided for all youth; (3) higher education should not be monopolized by any special class or race.

As a leader in education, Du Bois challenged not only the tradition of racial segregation in the schools but also the accommodationist ideology of Booker T. Washington. The major difference between the two men was that Washington sought change that was evolutionary in nature and did not upset the social order, whereas Du Bois demanded immediate change. Du Bois believed in educated leadership for blacks, and he developed a concept referred to as the “talented tenth”, according to which 10 percent of the black population would receive a traditional college education in preparation for leadership.

It can be inferred from the last paragraph that()

A. many blacks were prepared for leadership

B. Du Bois was in favor of “elite education” for blacks

C. Washington and Du Bois had never been friends

D. only the top 10 percent were worth educating

题型:填空题

调速汽门重叠度为什么不能太小?

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