中学

已知a5-a4b-a4+a-b-1=0，且2a-3b=1，则a3+b3的值等于______．

已知：|2x-10|+（y+2）2=0，求xy的值．

(北京卷)32. --- Where did you put the car keys？--- Oh, I ________ I put them on the chair because the phone rangas I ______ in.
A. remembered ; comeB. remembered ; was comingC. remember ; comeD. remember ; was coming

．2009年我国面临650万大学生就业问题。政府和教育部门采取多项措施促进大学生就业，引导和鼓励大学生面向基层。如果你是一名大学生，作出的正确选择应该①符合正确的就业观②符合社会现实和人民的需要③把追求个人价值放在首位④在个人与社会的统一中实现人生价值
A．①②③B．②③④C．①②④D．①③④

在数轴上，点A表示数-1，距A点2.5个单位长度的点表示的数是。

Directions: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context. When I was 8 years old, I once decided to run away from home. With my suitcase 36 and some sandwiches in a bag, I started for the front door and said to Mom, “I’m leaving.” “If you want to 37 , that’s all right,” she said. “But you came into this home without anything and you can leave the same way.” I 38 my suitcase and sandwiches on the floor heavily and started for the door again. “Wait a minute,” Mom said. “I want your 39 back. You didn’t wear anything when you arrived.” This really angered me. I tore my clothes off—shoes, socks, underwear and all—and 40 , “Can I go now？” “Yes,” Mom answered, “but once you close that door, don’t expect to come back.” I was so 41 that I slammed (砰地关上) the door and stepped out on the front porch. 42 I realized that I was outside, with nothing on. Then I noticed that down the street, two neighbor girls were walking toward our house. I ran to 43 behind a big tree in our yard at once. After a while, I was 44 the girls had passed by. I dashed to the front door and banged on it loudly. “Who’s there？” I heard. “It’s Billy! Let me in!” The voice behind the 45 answered, “Billy doesn’t live here anymore. He ran away from home.” Glancing behind me to see if anyone else was coming, I begged, “Aw, c’mon, Mom! I’m 46 your son. Let me in!” The door inched open and Mom’s smiling face appeared. “Did you change your 47 about running away？” she asked. “What’s for supper？” I answered. (277 words)
A. packed
A.returnedB.cleanedC.repaired

某市在今年4月份突遇大风，冰雹灾害性天气，造成直接经济损失5000万元．5000万元用科学记数法表示为（）
A．5000万元B．5×102万元C．5×103万元D．5×104万元

1-2的相反数是______，绝对值是______，倒数是______．

已知有理数a等于它的相反数，有理数b等于它的倒数．求a2008+b2005的值．

若代数式3x2﹣2x+5的值是6，则代数式6x2﹣4x﹣9的值是（）。

计算：（-3ab3）2=（）

某店进了一批货，有两种方案出售．方案一：月初出售，可获利2000元，然后将本和利再去投资．到月未又可获利5%；方案二：月末售出这批货，共可获利2500元，但要付50元的保管费。（1）写出按方案一出售这批货的总利润y（元）与这批货的成本x（元）之间的关系式；（2）要想获得较高的利润，请问这批货应按哪种方案出售。

已知：A=4x2-4xy+y2，B=x2+xy-5y2，求（3A-2B）-（2A+B）的值．

垂周分裂所形成的新细胞壁和器官表面垂直。()
A．正确B．错误

因式分ab-a=______．

已知代数式x+2y的值是3，则代数式2x+4y+1的值是（）。

下列函数的图象，与y轴交点在x轴上方的是[]
A．y=﹣xB．y=x﹣1C．y=﹣5+3xD．y=﹣2x+1

下列对于细菌和真菌的叙述中，正确的是()
A．它们都过着寄生或腐生的生活B．它们都很小，必须借助于显微镜才能看见C．细菌都危害人体健康，真菌营养价值高，可以食用D．细菌没有成形的细胞核，真菌具有真正的细胞核

“中国国家馆”作为2010年上海世博会的主题场馆，充分体现了中国文化的精神与气质．资料表明，在建设过程中使用的一种工艺，需要对中国馆的大台阶进行约5.4×107次加工．其中5.4×107表示的数为（）
A．5400000B．54000000C．540000000D．5400000000

下列函数的图象，不经过原点的是（）
A．y=3x2B．y=2x2C．y=（x-1）2-1D．y=3x