某镇通过调查得知，全镇平均人口数为 36 800人，其中65岁以上人口数为1840人

患者女性，52岁。右侧胸痛、刺激性咳嗽3周，咳痰带血2周。查体：气管居中，右胸叩诊浊音，呼吸音消失。X线胸片示右侧大量胸腔积液，为血性，积液找到癌细胞，为腺癌。

有人提出进行胸膜粘连和胸腔闭锁术，其指征主要取决于（）。

A.肿瘤的组织学类型，恶性程度高者指征较强

B.原发病灶是否得到控制

C.胸腔积液增长速度和压迫症状

D.无区域性淋巴结转移

E.肿瘤对化学治疗的敏感性

下列何项不是独活寄生汤的功用（）

A.补肾

B.清热

C.祛风祛风

D.补血

E.止痛

杂链高分子

对运行中的高、低压电流互感器二次侧接地的要求是（）

A.高压互感器二次侧应有一个固定的接地，但不应在回路其他处有第二个接地点

B.高压互感器二次侧应有多个接地点，以避免带来接地误差

C.高压互感器二次侧可不接地

D.低压互感器二次侧必须接地，以避免带来接地误差

Electronic mail has become an extremely important and popular means of communication.
The convenience and efficiency of electronic mail are threatened by the extremely rapid growth in the volume of unsolicited commercial electronic mail. Unsolicited commercial electronic mail is currently estimated to account for over half of all electronic mail traffic, up from an estimated 7 percent in 2001, and the volume continues to rise. Most of these messages are fraudulent or deceptive in one or more respects.
The receipt of unsolicited commercial electronic mail may result in costs to recipients who cannot refuse to accept such mail and who incur costs for the storage of such mail, or for the time spent accessing, reviewing, and discarding such mail, or for both. The receipt of a large number of unwanted messages also decreases the convenience of electronic mail and creates a risk that wanted electronic mail messages, both commercial and noncommercial, will be lost, overlooked, or discarded amidst the larger volume of unwanted messages, thus reducing the reliability and usefulness of electronic mail to the recipient. Some commercial electronic mail contains material that many recipients may consider vulgar or pornographic in nature.
The growth in unsolicited commercial electronic mail imposes significant monetary costs on providers of Internet access services, businesses, and educational and nonprofit institutions that carry and receive such mail, as there is a finite volume of mail that such providers, businesses, and institutions can handle without further investment in infrastructure. Many senders of unsolicited commercial electronic mail purposefully disguise the source of such mail.
Many senders of unsolicited commercial electronic mail purposefully include misleading information in the messages’ subject lines in order to induce the recipients to view the messages. While some senders of commercial electronic mail messages provide simple and reliable ways for recipients to reject (or "opt-out" of) receipt of commercial electronic mail from such senders in the future, other senders provide no such "opt-out" mechanism, or refuse to honor the requests of recipients not to receive electronic mail from such senders in the future, or both.
Many senders of bulk unsolicited commercial electronic mail use computer programs to gather large numbers of electronic mail addresses on an automated basis from Internet websites or online services where users must post their addresses in order to make full use of the website or service.
The problems associated with the rapid growth and abuse of unsolicited commercial electronic mail cannot be solved by the government alone. The development and adoption of technological approaches and the pursuit of cooperative efforts with other countries will be necessary as well.

The unwanted e-mail problem can be solved if ______.

A. the government takes action
B. a new technology is adopted
C. more people are aware of the problem
D. joint efforts are made and new technology is used