设向量a与b的夹角为θ,定义a与b的“向量积”:a×b是一个向量,它的模|a×b

题型:选择题

问题:

设向量
a
b
的夹角为θ,定义
a
b
的“向量积”:
a
×
b
是一个向量,它的模|
a
×
b
|=|
a
|•|
b
|•sinθ
,若
a
=(-
3
,-1),
b
=(1,
3
)
,则|
a
×
b
|
=(  )
A.
3
B.2C.2
3
D.4
考点:平面向量的应用
题型:选择题

女性,32岁。哮喘史10年,近年来发作频繁,3天前因搬家劳累导致重度发作,口服氨茶碱和沙丁胺醇(舒喘灵)未缓解,有加重趋势 |

A.口服茶碱控释片

B.静脉输注甲泼尼松(甲基强的松龙),雾化吸入β受体激动剂

C.口服泼尼松(强的松),短期使用(1周)

D.吸入异丙肾上腺素

E.使用麻黄碱(麻黄素)

题型:选择题

Have you ever suddenly felt that someone you know was in trouble ― and he was? Have you ever dreamed something that came true later? Maybe you have ESP.

ESP stands for Extra Sensory Perception. It may be called a sixth sense. It seems to let people know about events before they happen, or events that are happening some distance away.

Here is an example: A woman was doing washing. Suddenly she shouted, “My father is dead! I saw him sitting in the chair!” Just then, a telephone came. The woman’s father had died of a heart illness. He died sitting in a chair.

There are thousands of stories like this on record. Scientists are studying them to find out what is behind these strange mental messages. Here’s another example —— one of hundreds of dreams that have come true.

A man dreamed he was walking along a road when a horse and carriage came by. The driver said, “There’s room for one more.” The man felt the driver was Death, so he ran away. The next day the man was getting on a crowded bus. The bus driver said, “There’s room for one more”. Then the man saw the driver’s face was the same face he had seen in the dream. He wouldn’t get on the bus. As the bus drove off, it crashed and burst into fires. Everyone was killed!

Some people say stories like these are lies or coincidences. Others say that are ESP in true, from studies of ESP, we may some day learn more about the human mind.

小题1:ESP lets people know about _________.

A.their dream

B.events after they happen

C.events before they happen

D.heart illness小题2:The example of the man shows the ability to _______.

A.avoid traffic accidents

B.know the good and bad of a person

C.know about the events happening some distance away

D.sense a danger that will happen later on小题3:The best title of this passage is _________.

A.Sixth Sense

B.The Human Mind

C.A Big Lie

D.A Terrible Dream

题型:选择题

民族是历史上形成的具有共同的语言、区域、经济生活及心理素质的( )

A.稳定的共同体
B.固定的群体组织
C.固定的行政组织
D.稳定的宗教组织

题型:选择题

驾驶车辆向右变更车道时,应提前开启右转向灯,注意观察,在确保安全的情况下,驶入要变更的车道。

题型:选择题

原始凭证是由( )取得或填制的

A.总账会汁

B.业务经办单位或个人

C.会汁主管

D.出纳员

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