患者，女，56岁，5年前患乳腺癌手术治疗，术后化疗半年余。半年前发现在左锁骨上淋巴结

I、Ⅱ两小题只选做一题，如果两题全做，只按I题计分．

I5月31日为“世界无烟日”．吸烟会产生尼古丁（C₁₀H₁₄N₂）、烟焦油、一氧化碳等多种有害物质，不仅影响自身健康，对他人健康也有害．

（1）尼古丁属于______（选填“有机”或“无机物”）．

（2）乱扔烟头，会引起火灾．从燃烧条件分析，烟头引起火灾的原因是______．

（3）CO是有毒气体，能使人中毒的原因是______．

Ⅱ在农业生产中，土壤的改良，化肥、农药的合理施用，对农作物的高产丰收具有重要作用．

（1）农业生产中常用熟石灰改良______（选填“酸性”或“碱性”）土壤．

（2）农药波尔多液是用石灰乳[Ca（OH）₂]和硫酸铜溶液按一定比例配制的，配制过程中，发生的基本反应类型为______．

（3）铵态氮肥不能与碱性物质混合施用的原因是______．

当自行设定一个折现率ic对一个项目进行折现时，下列各项有关净现值、现值指数和内部收益率之间的关系不正确的是( )。

A．当NPV>0时，PI>1，IRR>ic

B．当NPV＝0时，P1=1，IRR＝ic

C．当NPV<0时，PI<1，IRR当NPV>0时，PI<1，IRR

ZAO Picture is a specialist company that deals in works of art. It acquired three paintings signed by a famous artist and decided to make these available for sale.The company sent letters to Nikolai, Peter and Svetlana stating the following:‘ZAO Picture is prepared to offer you an exclusive bargain. You have the opportunity to purchase a signed painting (full description given) by the famous artist Chaikin for 500.000 roubles. In order to secure your purchase please reply, enclosing full payment, by 13.00 hours on 1 February 2008’.Nikolai replied to the letter and sent full payment for the painting, but his reply did not reach ZAO Picture until 3 February 2008. Peter’s response was to send a remittance of 450.000 roubles, with a letter stating that he was prepared to purchase the painting but as a valued customer expected a discount of 10%. Svetlana did not reply, but the general director of ZAO Picture was certain that as an enthusiastic art collector she would wish to accept the offer and sent her a painting with an invoice for 500.000 roubles.Required:

(a) Explain whether the letters sent by ZAO Picture to the three clients were offers which, if accepted, formed the basis of binding contracts. (4 marks)

“福音”是什么意思？

下列叙述中，属于网络安全技术研究主要涉及的方面是( )。
Ⅰ、安全攻击 Ⅱ、病毒预防 Ⅲ、安全机制
Ⅳ、访问控制 Ⅴ、安全服务

A) 全部
B) Ⅰ、Ⅱ、Ⅲ和Ⅳ
C) 仅Ⅰ、Ⅲ和Ⅴ
D) 仅Ⅰ、Ⅱ和Ⅲ