用反证法证明命题“如果a＞b，那么a3＞b3“时，下列假设正确的是（ ） A．a3

柴油机运转中排气冒白烟的原因有哪些？

试题(1)、(2) 随着因特网技术的快速发展，企业门户已经成为企业优化业务模式、扩展市场渠道、改善客户服务，以及提升企业形象和凝聚力的重要手段。按照实际应用类型，企业门户可以划分为4类，分别是企业网站、企业信息门户、企业____(1)____门户和企业应用门户。为了支持跨越多个应用系统的工作流程，企业门户主要采用____(2)____技术对现有应用系统的处理逻辑进行整合。

1（）

A．数据

B．产品

C．过程

D．知识

根据以下业务背景资料，回答（一）～（五）题的相关问题。2010年7月1日，上海进出口贸易公司（SHANGHAI IMPORT AND EXPORT CO., LTD.）与澳大利亚客户（MANDARS IMPORTS CO.,LTD）签订了一份出口女式牛仔裙（.Ladies Denim Skirt）的合同（合同号为PU20107），并指派外贸跟单员小王负责此笔业务跟单合同的主要内容如下：Fabric & Construction : 99% cotton 1% polyester with spandex 11S ×16S +70D/88×46 Washing: Stone washed Packing: Flat pack, 1 piece/polybag1 dozen into a big polybag, assorted sizes per polybag, 4 big polybags into an export carton. Export carton must be p. Maximum sizes of export cartons: Length Width Heightcm 60 42 48 ColourBlue/grey Shipping mark of the cartons As per our information Hangtag: MANDARS Main label: MANDARS Washing label: With correct compositon & washing instruction Samples: Pre-production samples: 3 pieces in size 38 before 15th July,2010（ETD Shanghai）by DHL The pre-production samples should be made after the fabric has been tested and passed by STR Shanghai Branch, （上海胜邦质量检测分公司）then will be sent to customer’s quality assurance department. “GO” for production can only be given after their approval. Lab Dip samples:as confirmed by our assurance quality department on 5th July,2010 Shipping samples: 2 pieces in size 38 on/about 5 days after shipment Payment: 30 % deposit with order by T/T, the balance against copy of B/L Price terms & total amount: USD 8.00 per piece FOB Shanghai, USD144000.00 Quantity: 18000 pieces, size and color assortment:

5% more or less in the quantity and amount are allowed. Shipment: 20th August, 2010 from Shanghai to Sydney, Australila by COSCO as carrier , partial and transshipment allowed Shipping agent: Shipment should be made by Shanghai Jingde Int’l Forwarding Co.,Ltd.. Tel86-21-62228123，AttnMr.Liu Purchase conditions: All garments manufacturers must meet the minimum manufacturing standards, comply with the SA8000 and all garments should be AZO-free and no nickel in press buttons is used.

该合同对于pre-production samples是否可用替代面料制作？

某产品单位变动成本10元，计划销售1 000件，每件15元，问固定成本应控制在 ( )元之内才能保本。

A．5000
B．10000
C．15000
D．150

送电前应确认电动扳手上开关断开状态，以防送电后电动扳手突然转动，存在造成人员伤害的危险。