题海网，海量题库；找题库、找试卷、找答案就上题海网。

已知函数f(x)＝a^x ， 其中a>0，且a≠1，如果以P(x₁ ， f(x₁))，Q(x₂ ， f(x₂))为端点的线段的中点在y轴上，那么f(x₁)·f(x₂)等于(   )

根据课文默写，并写出相应的作者或篇名。 

下图为“我国人均资源占有量与世界平均水平比较图”，读图完成下面小题。

卫星自主改变运行轨道的过程称为变轨。为节省发射火箭燃料，可以把卫星先发射到转移轨道（椭圆轨道），卫星处于远地点时，点火变轨，进入绕地同步轨道。下列说法正确的是（   ）

电工师傅常用一只额定电压为220V的灯泡L₀（检验灯泡）取代保险丝来检查新安装的照明电路中每个支路的情况，如图所示．当S闭合后，再分别闭合S₁、S₂、S₃（每次只能闭合其中之一）时，可能出现以下三种情况，试判断（选填：“短路”、“断路”或“正常”）：

（1）L₀不亮，说明该支路 ．

（2）L₀正常发光，说明该支路 ．

（3）L₀发光呈暗红色，说明该支路 

下列生活中常见的现象，属于化学变化的是（   ）

读“甲城市地租等值线示意图”（图甲）以及“甲城市某区域日均地铁分时段客运量统计图”（图乙），图甲中所示地区（    ）

阅读理解

Active Challenge

Weight loss camp for girls aged 13—18in Canada

Location: Beautiful Bear Creek Outdoor Center Near Ottawa, Ontario

Season: July 2nd—August 28th

Capacity: 40 Activities include: hiking, rafting, canoeing, yoga, cooking, camp skills, mountain biking, nutrition classes, swimming, fitness classes etc.

Choose what you like!

Active Challenge is a weight loss program specially for young women. The burden of being overweight is heavier than just the extra pounds. We use outdoor adventures to challenge the girls, to give them something to draw strength from.

Because you'll be losing weight alongside young women just like you, you'll find no one laughing at you and you'll help each other. At Active Challenge you'll make lifelong friends with young women of your own age and learn to love new adventurous activities.

Unlike any other weight loss program, Active Challenge is designed so you'll lose weight and have the strategies and skills to keep the weight off forever. Active Challenge does not put you on a diet. We follow the Canada Food Guide to healthy eating and exercise appropriate portion control. We help you develop healthy habits.

The staff at Active Challenge combine experienced outdoor adventure professional with highly qualified clinicians. All of us are absolutely devoted to helping you achieve lasting behavioral change and weigh loss. Most of all we are devoted to having a great time doing it.

Pre—Camp: Upon registration in Active Challenge, a registration package will be sent out to you with forms to be completed before camping as well as program preparation materials, an introduction to Active Challenge and pre—program personal challenge assignments to get you on your way toward a healthier you.

Post—Camp: Our post program is designed to keep you focused and remind you of the goals that you set during the camp. We will send you home with your personal meal and exercise plan and keep in touch with you for a full three months after the camp ends through letters, emails and phone calls, tracking your progress and giving you strategies and support.

“观万国之势，能变则全，不变则亡，全变则强，小变仍亡”是哪一派别的观点（    ）

某件衣服标价200元，按标价的6折出售可获利20%，则这件衣服的进价为（   ）元

产品说明书也称用户手册，它是指导用户消费的文书。产品说明书的结构组成部分一般包括（    ）

下列叙述错误的是（   ）

利用你所学过的知识，请根据下图信息回答问题：

（1）锶属于元素（选填“金属”或“非金属”）．
（2）锶元素的原子序数为 ， 相对原子质量为 ．
（3）如图2所表示的粒子的化学符号是 ．

某省是文化资源大省，但是文化产业不发达。近年来，该省立足自身优势，大力发展文化产业，使其成为国民经济的支柱性产业。抓住重塑市场主体这一关键环节，打破地区、部门、行业和所有制限制，以资本为纽带，以市场为导向，培育和扶持重点文化企业集团，提高集约化经营水平和产业集中度。依托历史文化资源，打造有地域特色和民族特色的文化产品。学习借鉴全国其他地区的成功经验，将科技运用到文化产业发展中，大力发展高科技型文化产业。

结合材料，分析该省在文化发展方面的措施是如何体现矛盾分析法的。

—What are you doing, Mr. Elephant?

—I am drinking water with my trunk.

和是最基本的框架，其中框架的稳定性最好，利用它可以增强各种框架结构的稳定性。

晚上在桌面上铺一张白纸，把一块平面镜放在纸上（镜面朝上），让手电筒的光正对着平面镜照射，从侧面看过去，白纸比镜子（选填“亮”或“暗”），这时在白纸上发生了．

在下面的图形中，

计算．

=

=

4x-8>18不是方程。（    ）