在△OAB中,O为坐标原点,横、纵轴的单位长度相同,A、B的坐标分别为(8,6)

题型:解答题

问题:

在△OAB中,O为坐标原点,横、纵轴的单位长度相同,A、B的坐标分别为(8,6),(16,0),点P沿OA边从点O开始向终点A运动,速度每秒1个单位,点Q沿BO边从B点开始向终点O运动,速度每秒2个单位,如果P、Q同时出发,用t(秒)表示移动时间,当这两点中有一点到达自己的终点时,另一点也停止运动。

求:(1)几秒时PQ∥AB;

(2)设△OPQ的面积为y,求y与t的函数关系式;

(3)△OPQ与△OAB能否相似,若能,求出点P的坐标,若不能,试说明理由。

考点:求二次函数的解析式及二次函数的应用相似三角形的判定
题型:解答题

患者,男,12岁,因右前臂擦伤后肿痛伴高热5天来诊。查体:体温40℃,呼吸20次/分,右前臂局部红肿,压痛,与正常皮肤无明显分界。血白细胞15.9×109/L,中性粒细胞占85%。经大剂量抗生素治疗3天及应用退热药物仍不能控制,病变范围迅速扩大。

该患者最可能的诊断为

A.右前臂疖
B.右前臂痈
C.右前臂丹毒
D.右前臂蜂窝织炎
E.右前臂淋巴管炎

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American black bears appear in a variety of colors despite(尽管) their name. In the eastern part, most of these bears have shiny black fur, but in the west they grow brown, red, or even yellow coats. To the north, the black bear is actually gray or white in color. Even in the same litter(胎), both brown and black furred bears may be born.

Black bears are the smallest of all American bears, ranging in length from five to six feet, weighing from three hundred to five hundred pounds. Their eyes and ears are small and their eyesight and hearing are not as good as their sense of smell. Like all bears, the black bear is timid and rarely dangerous, but if attacked, most can climb trees or cover ground at great speed. When angry or frightened, they are formidable(可怕的) enemies.

Black bears feed on leaves, roots, fruit, insects, fish, and even larger animals. One of the most interesting characteristics of bears, including the black bear, is their winter sleep. Unlike squirrels and many other woodland animals, bears do not actually sleep through the winter months. Although the bear does not eat during the winter months, sustaining(维持) itself from body fat, its temperature remains almost normal, and it breathes regularly four or five times per minute.

Most black bears live alone, except during the mating(交配) season. They prefer to live in caves. Baby black bears are born in January or February after a gestation(怀孕) period of six to nine months, and they stay with their mother until they are fully grown or about one and a half years old. Black bears can live as long as thirty years in the wild, and even longer in some nature reserves.

小题1:American black bears may have ___________ colours according to the passage.

A.four

B.five

C.six

D.seven小题2:Black bears have a good sense of _________.

A.hearing

B.smell

C.eyesight

D.taste小题3:Which of the following statements is RIGHT?

A.Black bears sleep through the winter months.

B.Black bears can live up to 30 years old.

C.Black bears are the smallest bears in the world.

D.Most black bears live in a group.小题4:What does the underlined word “enemies” refer to?

A.Black bears’ enemies.

B.Black bears.

C.Other large animals.

D.American bears.小题5:We cannot read the passage ___________.

A.in a newspaper

B.on the Internet

C.in a book

D.in an advertisement

题型:解答题

蛤粉炒阿胶善于()。

A.滋阴补血

B.清热化痰

C.止血安络

D.益肺润燥

E.治血虚萎黄

题型:解答题

如果存在如下过程:  Private Function FMax(a( )As Integer)   Dim First As Integer,Last As Integer,i As Integer   First=LBound(A)    Last=UBound(A)    Max=a(First)   For i=First To Last    If a(i) > Max Then Max=a(i)   Next i   FMax=Max  End Function  在窗体上添加一个命令按钮,然后编写如下事件过程:  Private Sub Command1 Click( )    ReDim m(1 To 4) As Integer    m(1)=20:m(2)=30:m(3)=50:m(4)=100    c=FMax(m)    Print c  End Sub  单击命令按钮,其输出结果为【 】。

题型:解答题

小儿腹部胀满,叩之有波动感,应首先考虑的是

A.气滞
B.食积
C.腹水
D.疳证
E.虫积

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