下列各式中，能用平方差公式计算的是（ ） A．（-a-b）（a+b） B．（-a

A Sports体育运动
Many animals engage in play，but homo sapiens is the only animal (1) have invented sports.Since sports are an invention，a part of culture (2) than an aspect of nature，all definitions of sports are somewhat arbitrary. (3) sports are a human universal found in every known culture or a (4) unique to modern society depends upon one’s definition of sports.Men and (5) have always run，jumped，climbed，lifted，thrown， and wrestled，but they have (6) always performed these physical activities competitively. Although all literate societies seem to (7) contests of one sort or another in which men， and sometimes women， (8) in displays and tests of physical skill and prowess，sports may be (9) defined as physical contests performed for their own sake and not for (10) ulterior end.According to this strict definition，neither Neolithic hunters nor contestants (11) religious ceremonies such as the ancient Olympic Games were engaged in sports. (12) on the stipulation that sports must be performed for their own sake (13) the paradoxical elimination of many activities which are usually thought of as (14) ，such as exercises done for the sake of cardiovascular fitness，races run (15) satisfy a physical education requirement，ball games played to earn a paycheck. (16) definition also means abandonment of the traditional usage in which"sport，"derived (17) Middle English disporter，refers to any light hearted recreational activity.In the. (18) of some 18th- century aristocrats，a game of backgammon and the seduction of (19) milkmaid were both considered good sport，but this usage of the term (20) become archaic.

下列属于现代发酵技术应用的是（　　）

A．制酱

B．制醋

C．制腐乳

D．制青霉素

下列实例中，通过做功改变物体内能的是（　　）

A．将沸水倒入茶杯后，茶杯变得烫手

B．将冰冻食物放入温水中解冻

C．冬天，晒太阳取暖

D．超载货车的刹车片经常处于高温状态而炭化，容易造成刹车失灵

高热体温多在（）

A.38℃以上

B.38.5℃以上

C.39℃以上

D.39.5℃以上

E.40℃以上

阅读下列材料：罗斯福新政从一开始就遭到一部分资本家的反对，他们嫌罗斯福太迁就工人，课了垄断资本家的商税。报纸上连篇累牍咒骂罗斯福是“向富人敲竹杆”。说罗斯福天天都吃“烤百万富翁”。在关于《社会保障法》的听证会上，有人高喊：“这个法案是从《 * * 党宣言》第十八页逐字逐句抄下来的”。胡佛在《国家工业复兴法》通过之后对政府干预经济生活的规定也感慨说：“这简直是法西斯！”请回答：

“罗斯福新政”对当时的美国起到什么作用？