设向量a=(1,-2),b=(-3,x),若a⊥b,则x=______.

题型:填空题

问题:

设向量
a
=(1,-2)
b
=(-3,x)
,若
a
b
,则x=______.
考点:用数量积判断两个向量的垂直关系
题型:填空题

石粒类饰面是将水泥为______、石粒为骨料的水泥石粒浆抹于______,然后用水洗、斧剁、水磨等手段除去______露出以石粒的颜色、质感为主的饰面做法。

题型:填空题

句型转换  (共20空,每空0.5分,满分10分)

小题1:The government calls on every citizen to contribute to building a harmonious society.

The government calls on every citizen to _______ _______ to building a harmonious society.

小题2:Nowadays, it is possible that we find it hard to understand Old English because it is made up of a mixture of different languages.

Nowadays, we _______ _______ to find it hard to understand Old English because it _______ _______ a mixture of different languages.

小题3:The children quickly ran away and I couldn’t see them anywhere before I could say a word.

The children quickly ran away and were _______ to _______ _______ before I could say a word.

小题4: It is known to us that making others embarrassed in public is impolite.

_______ is _______ to us, it is impolite to _______ others in public.

小题5:Judging from the disappointed look on his face, he failed the test.

Judging from the disappointed look on his face, _______is _______ that he failed the test.

小题6:Besides knowledge, responsibility and respect should also be taught to students.

_______ _______ knowledge, responsibility and respect should also be taught to students.

小题7:On Tomb-sweeping Day, people go tomb sweeping to remember those who have passed away.

On Tomb-sweeping Day, people go tomb sweeping _______ _______ of those who have

passed away.

小题8:Most people believe that families play a very important role in education.

Families are _______ _______ play a very important role in education.

题型:填空题

妊娠期内药物致畸最敏感的时期是()。

A.妊娠半个月以内

B.妊娠3周至12周

C.妊娠4~9个月

D.妊娠9个月以后

题型:填空题

李某、胡某和张某分别是某影片的编剧、导演和制片人。根据著作权法及相关规定,下列说法哪些是正确的

A.张某享有该影片的著作权

B.胡某享有该影片的著作权

C.胡某享有署名权

D.李某有权就该影片的剧本单独行使著作权

题型:填空题

下面不是肾细胞癌特点的是()

A.是起源于近端肾小管上皮细胞的恶性肿瘤

B.无痛性血尿、腰痛、季肋部肿物是其主要症状

C.透明细胞癌是最常见的类型

D.通常易发生淋巴道转移

E.免疫组化:CK8、EMA、CEA阳性,Vimentin阴性

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