昆虫纲是动物界种类最多、数量最大的类群,与人类经济和健 康有极密切的关系,是医学节肢动物中最重要的组成部分。 昆虫( insect)成虫体分头、胸、腹三部分(图16-1)。 图16-1昆虫外部形态模式图(第四版教材P229图20-1) 头部有触角( antenna)1对,为感觉器官,司嗅觉和触觉;复 眼( compound eyes)1对。头部前方或腹面有取食器官,称为口器 ( mouthparts),通常由上唇( labrum)、上颚( mandible)、舌 ( hypopharynx)、下颚( maxilla)及下唇( labium)组成

Corporate restructuring 1960s- Mergers of unrelated firms formed huge conglomerates 1980s-Investors purchased conglomerates and sold off the pieces as independent companies. 1990s- Strategic mergers of related firms to create synergies

Innovations in Risk Management Futures contract a contract to buy or sell a stated commodity or financial claim at a specified price at some specified future time

Liquid asset management S CASH- motives for holding casha Transactions: to meet cash needs that arise from doing business. Precautionary: having cash on hand for unexpected needs Speculative: to take advantage of potential profit-making situations

Dilemma: Should the firm use retained earnings for: a) financing profitable capital inⅴ estments? b)Paying dividends to stockholders

2 concepts that enhance our understanding of risk... 1) Operating Leverage affects a firm's business risk. 2) Financial Leverage affects a firm's financial risk

Top Creators of shareholder value 1999 invested cost of MVA capital return capital Microsoft3282571095456.16%12.64 Gen elect285,320652981929911.92 Intel

Three Measures of a Project's Risk Project Standing Alone risk

Capital Budgeting: the process of planning for purchases of long term assets。 ° example Suppose our firm must decide whether to purchase a new plastic molding machine for $125.000. How do we decide? will the machine be profitable? Will our firm earn a high rate of return on the investment?

Characteristics of Bonds o Bonds pay fixed coupon ( interest) payments at fixed intervals(usually every 6 months)and pay the par value at maturity