懂的進,要完整解答+正確率=積分給~
1、已知x、y是有理數(shù),且 | 3x – 4 | + (3y + 7 )² = 0,求：
(1) x² + y² (2) x²– 2xy + y²
2、某校六（1）班在春游分組時,同學(xué)們作這樣安排各中隊長任春游小組長,每人負(fù)責(zé)7名同學(xué).,這樣有一組人數(shù)不足,若每組減少一人則多余3人,已知六（1）班人數(shù)在30～50之間,問該班總?cè)藬?shù)可能是多少?
3、棱長分別為3厘米,5厘米,4厘米的兩個長方體拼湊成一個長方體,它們的表面積最多減少多少平方厘米?
4、已知長方體的長,寬,高之比是5：4：3,用一根長為240厘米的鐵絲,制作這個長方體的模型,求此長方體的表面積.
5、一個角的補角與它的余角之比為3∶1,求這個角的度數(shù).
6、線段AB=54cm,C是AB的中點,D是AC上的一點,且CD=2AD,E是BC的中點,求線段DE的長.
( )1.A lot of land becomes deserts because many trees are ____ by people.
A.cut off B.cut in C.cut back D.cut down
( )2.The police are trying to ____ the real murderer.
A.see B.look C.find out D.watch
( )3.The company promises to ____ a meal for each worker.
A.bring B.Provide C.have D.take
( )4.— ____ can we save water?
— By turning off a running tap.
A.When B.Why C.Where D.How
( )5.— How are you feeling today?— ____.
A.I don’t like it B.Thank you
C.Not too bad,thanks D.I’m sorry to hear that
( )6.Let’s the menu first.
A.have a look B.look C.have a look at D.see
( )7.There are many things in the supermarket.will you go to first?
A.Where B.Which section C.What D.When
( )8.Mr Smith has ____ 8-year-old daughter who is very lovely.
A.a B.an C.the D./
( )9.Mr White has more money than Mr Black.But he doesn’t enjoy ____.
A.himself B.him C.his D.he
( )10.Kitty won first prize in the English contest.Her parents are proud ____ her.
A.from B.of C.at D.to
完形填空
The earth is our home.We must take good care of it.That is to say we must (1)k_________ the land,air and water clean.
But man began to (2)p__________ the earth when he first made a fire,washed his clothes in the river and threw dirty things onto the ground.Many years ago,pollution was not so serious(嚴(yán)重的) because there were not so many (3)p__________.There was enough clean air,land and water.When the land or the river was dirty in one place,man moved to (4)a___________ place.But now man is slowly polluting the whole world and there is (5)n__________ enough clean air nor clean land.The more people in one place,the more (6)p____________ there will be.
When is this all to end?Is it possible to get rid of(消除) pollution?We are (7)g____________ to say that people have come to know the danger of pollution and a large number of them are working hard to protect our earth.
英語選擇題不要ABCD亂寫~