男，60岁，排尿困难，CT前列腺后叶增大，密度低，增强后左叶内可见16mm×22mm

下列因式分解中，正确的是（　　）

A．x²-4y²=（x+4y）（x-4y）

B．x²-y²=（x-y）²

C．x（x-y）-y（y-x）=（x-y）²

D．10x²-5x=5x（2x-1）

如图所示，小安和小虹分别用各自的光具座做“探究凸透镜成像规律”的实验。

（1）小安在实验中不小心将毛玻璃制成的光屏弄碎了，小安用一个与光屏等大的平面镜来代替光屏，却很难找到像，这是因为平面镜表面很光滑，光在上面发生了_______反射，所以不易观察到像。

（2）实验时平面镜还有些歪，小安将其左右移动，眼尖的小虹观察到近旁的白墙上出现烛焰的像，这是由于平面镜可以有______________的作用，生活中所使用的_______的成像过程与此相似。

遥感技术、地理信息系统、全球定位系统等现代化技术在国土整治中具有重要作用。据此回答6一8题。

小题1:要对长江流域水灾灾情进行监测的理想途径是

A．人工监测

B．应用遥感技术

C．坐飞机目测

D．水上坐快艇监测小题2:要准确快捷地查询各地的灾害信息材料，主要依靠

A．传感器

B．遥感技术

C．地理信息系统

D．全球定位系统小题3:为防御台风危害要研究台风的中心位置及移动方向，对台风中心及移动方向信息的准确获得利用了

A．RS技术

B．GIS技术

C．GPS技术

D．观测资料

胸骨左缘2、3肋间有Ⅱ—Ⅲ级柔和的收缩期吹风样杂音，P₂亢进、固定分裂（）

A．房间隔缺损

B．室间隔缺损

C．法洛四联症

D．动脉导管未闭

E．艾森门格综合征

Personal computers are used by one person at a time. The largest personal computer, or PC.S, can fit on a (1) . Some of these (2) have more than one microprocessor. (3) the primary processor, which is a general-purpose device, a PC may have one or more processors to (4) special kinds of work. Some machines, (5) , have maths processors, others have graphics processors to help process photographs and other illustrations. Still others have (6) processors.

Office workers also use PCS that are not (7) to a network. These machines are used for (8) tasks as word processing, performing financial calculations, and organizing and (9) bodies of information called databases. People use PCS at (10) for some of the same kinds of tasks. They use word processing programs for (11) communication, financial software for household budgets. Individuals also use their home computers to play (12) and to communicate (13) the internet.

Small, portable PCS are (14) with people who often work away from their desks. The (15) include laptop computers, which can be (16) on the lap; notebook computers, which are about the (17) of a loose leaf notebook; and palmtop, or handheld computers, which can be operated while (18) in the hand. Laptop and notebook computers have the same (19) as desktop computers. Palmtop computers have less power but still (20) some advanced capabilities. For example, they can process household financial data.

13（）

A. in

B. across

C. over

D. above