估算长6米、φ300mm圆钢的重量是多少？

下列的说法属于正确的是(    )

A．应该选用体积大的材料制造机器底座

B．应该选用体积的材料制造飞机

C．应该选用质量大的材料制造飞机

D．应该选用密度小的材料制造飞机

用数组表示线性表的优点是： (4) 。

A．便于插入和删除操作

B．便于随机存取

C．不需要占用一片相邻的存储空间

D．可以动态地分配存储空间

Applications put computers to praticalbusiness (1), but below the (2) it’s the heart of an operating system—the kernel that provides the technical wizardry to juggle multiple program, connect to networks and store(3).A traditional kernal provides all the functions for applications. The kemal (4) memory, I/O devices and parcels out processor time.

The kernel also supports security and fault (5) , which is the ablity to recover automatically when parts of the system fail.

2（）

A．ciphertext

B．hypertext

C．plaintext

D．supertext

某依法必须招标的修缮工程施工项目招标公告规定：投标人需具有公路工程施工承包一级和隧道工程施工专业承包一级资质；组成联合体投标的，联合体牵头人5年间必须具有5项类似工程施工业绩；在提交投标保证金后才能购买招标文件。
招标公告发布了4天，仅1家施工企业购买了招标文件。招标人经分析后认为：“5项类似工程施工业绩”的资格条件可能过高而影响潜在投标人参与竞争，于是决定将其修改为“2项类似工程施工业绩”。由于项目建设工期紧迫，招标人决定在招标文件中直接对上述资格条件进行调整，并按调整后的资格条件发售招标文件，同时在开标日15日前书面通知了购买招标文件的潜在投标人。最终共有9家投标人参加投标。为确保招标顺利进行，招标人要求各投标人放弃“因招标文件调整资格条件而影响其中标”的投诉权利，各投标人均按要求递交了书面承诺。
联合体投标人A由B公司、C公司、D公司组成，其签订的联合体协议约定公路工程施工由B公司承担，隧道工程施工由C公司、D公司承担(双方各承担50%的工作量)。B公司具有公路工程施工总承包一级和隧道工程施工专业承包二级资质，C公司具有公路工程施工总承包二级和隧道工程施工专业承包一级资质，D公司具有隧道工程施工专业承包一级资质。联合体投标人E由G、H、I三家公司组成，其中H公司为联合体投标人E的牵头人，G公司以自己的名义又单独提交了一份投标文件。其他投标人均为独立投标人。
经评审，投标人E为第一中标候选人。招标人确定E为中标人并与牵头人H公司订立了合同。因E仅具有2项类似工程施工业绩，具有5项类似业绩的第二中标候选人J以E不具备招标公告规定的资格条件为由向行政监督部门投诉，要求确认E的中标无效。

投标人J是否有权投诉？说明理由。

In Plato’s Utopia, here are three classes: the common people, the soldiers, and the guardians chosen by the legislator. The main problem, as Plato perceives, is to insure that the guardians shall carry out the intention of the legislator. For this purpose the first thing he proposes is education.

Education is divided into two parts, music and gymnastics. (46)Each has a wider meaning than at present: “music” means everything that is in the province of the muses, and “gymnastics” means everything concerned with physical training fitness. “Music” is almost as wide as what is now called “culture”, and “gymnastics” is somewhat wider than what “athletics” mean in the modern sense.

Culture is to be devoted to making men gentlemen, in the sense which, largely owing to Plato, is familiar in England. The Athens of his day was, in one respect, analogous to England in the nineteenth century: (47) there was in each an aristocracy enjoying wealth and social prestige, but having no monopoly of political power; and in each the aristocracy had to secure as much power as it could by means of impressive behavior. In Plato’s Utopia, however, the aristocracy rules unchecked.

Gravity, decorum and courage seem to be the qualities mainly to be cultivated in education. (48)There is to be a rigid censorship from very early years over the literature to which the young have access and the music they are allowed to hear. Mothers and nurses are to tell their children only authorized stories. Also, there is a censorship of music. The Lydian and Ionian harmonies are to be forbidden, the first because it expresses sorrow, the second because it is relaxed. (49)Only the Dorian (for courage) and the Phrygian (for temperance) are to be allowed, and permissible rhythms must be simple, and such as are expressive of a courageous and harmonious life.

As for gymnastics, the training of the body is to be very austere. No one is to eat fish, or meat cooked otherwise than roasted, and there must be no sauces or candies. People brought up on his regimen, he says, will have no need of doctors. Gymnastics applies to the training of mind as well. Up to a certain age, the young are to see no ugliness or vice. (50)But at a suitable moment, they must be exposed to “enchantments”, both in the shape of terrors that must not terrify, and of bad pleasures that must not seduce the will. Only after they have withstood these tests will they be judged fit to be guardians.

(50)But at a suitable moment, they must be exposed to “enchantments”, both in the shape of terrors that must not terrify, and of bad pleasures that must not seduce the will.