非接触非线式作战形式的主要特点有（） A.全纵深开展 B.多方向多手段实施 C.远程

中、高年级同学听科学家作报告中年级有84人参加，高年级参加的人数是中年级的3倍．听报告的一共有多少人？

根据不等式的性质，把下列不等式表示为x＞a或x＜a的形式：

（1）10x-1＞9x

（2）2x+2＜3

（3）5-6x≥2

Last spring, members of Alaska’s Troop 34, based in Fairbanks, trudged (跋涉) out into the snowy wilderness to take part in their state’s Take a Kid Trapping program. In many parts of the state, beavers （海狸）are pests and need to be controlled.

The 10－to－12－year－old girls found out where beavers lived, set traps, and skinned the two animals they caught. The girls hope to catch ten more beavers so that the entire troop can make mittens and hats with the fur. They also want to cook beaver meat.

Troop leaders and members say the Scouts are doing a good deed by helping control the state’s beaver population. But animal－rights activists say trapping is cruel. They want the Girl Scouts to stop in their tracks.

Beavers aren’t only causing a problem in Alaska. Residents in Sampson County, N.C. , have turned to a local committee to help them battle the growing beaver population there.

County landowners are frustrated after the county spent more than $ 50,000 in eight years trying to reduce the beaver population through a government program. The joint state and federal program included paying money to trappers for every beaver carcass  they trapped.

Many local residents say that the program didn’t work because there were too few trappers. That’s why the county set up its own committee to investigate other ways to control the area’s beaver population.

The county will rely on its own beaver－trapping program. It has hired a trapper to set traps in various areas. The county will pay $10 for every beaver carcass.

Why do many people say that beavers are a nuisance? For beavers to survive, they need lots of water. Water provides the large rodent （啮齿动物）with a place to hide from meat – eating animals. Beavers also store food underwater for the winter. When there’s not enough water in a particular area, beavers get busy building dams.

Beaver dams can cause major flooding and damage to the surrounding countryside as the animals cut down trees to use in their construction projects. Beavers build canals to transport heavy objects.

59．What is Alaska’s Troop 34?

A．A team of the Boy Scouts.     B．An army.

C．A team of the Girl Scouts.     D．A sports team.

60．Why does the troop hope to catch ten more beavers?

A．To fulfill their task.        B．To sell them for money.

C．To get enough fur.   D．To exchange them for mittens and hats.

61．Which of the following statements is true?

A．Sampson County has to find a new way to control the beaver population there.

B．The government program in Sampson County has proved to be a success.

C．The local government has controlled the number of beavers in the County.

D．More and more trappers now start to set traps in Sampson County.

62．Local residents hate beavers because they can ___________.

A．cause damage to dams

B．block up canals with heavy objects.

C．do great harm to construction projects.

D．badly damage the environment and cause floods.

普利策《世界报》业务活动有何基本特色。

（）叶片泵运转时，存在不平衡的径向力。

A、单作用

B、双作用

C、单作用或双作用

D、以上情况都不是