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问题 填空题

据统计，生态系统中，在输入一个营养级的能量中，大约有10%～20%（包括20%）的能量可以流动到下一个营养级（称为能量传递率），在H1→H2→…→H8这条生物链中，若H1提供的能量为107焦，则H8最多获得的能量为 ______焦．

答案

当能量传递率为20%时，H8获得的能量最大，

并且逐级传递时，各级获得的能量构成一个等比数列{an}，

首项a1=107，公比为q=20%，

故H8获得的能量为a8=107•（20%）7=107•

1
57
=27=128．

故答案为：128．

单项选择题

线性表最常用的操作是存取第i个元素及其前趋的值，则采用 ______ 存储方式节省时间

A．单链表

B．双向链表

C．单循环链表

D．顺序表
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问答题

Silicon Valley is a magnet to which numerous talented engineers, scientists and entrepreneurs from overseas flock in search of fame, fast money and to participate in a technological revolution whose impact on mankind will surely surpass the epoch-making European Renaissance and Industrial Revolution of the bygone age.
(46) With the rapid spread of the Internet since the early 1990s, and the relentless technological innovations generated through it, the information era is truly upon us, profoundly influencing and changing not only our lifestyle, but also the way we work, do business, think and communicate with others.
(47) The unprecedented success of the Valley is a testimony to the concerted international endeavors and contributions by people from diverse cultural and racial backgrounds, made possible by the favorable political, economic and intellectual climate prevailing, as well as the farsighted policies of the US government.
Many countries have, or are in the process of creating, their own "Silicon Valley". So far, none has as yet threatened the preeminence of the US prototype. What makes Silicon Valley such a Unique entity There are several crucial factors.
(48) First and foremost, it has the largest concentration of brilliant computer professionals and the best supporting services in the world, and easy access to world-class research institutions, like Stanford University, which continually nurtures would-be that the industry needs in order to move forward. Without these advantages, the Valley would be a different place.
Secondly, it actively encourages, or even exalts, risk taking. Hence, failure holds no terror and there is no shame attached to a failed effort. On the contrary, they will try even harder next time round. Such never-say-die approach is the sine qua non for the ultimate triumph in entrepreneurship and technological breakthrough.
(49) A third decisive factor is the vital role of venture capitalists who willingly support promising start-ups with urgently needed initial capital to get them started. Some would even give failed entrepreneurs a second chance if convinced that a fresh concept might lead to ultimate success.
(50) Of equal importance, bright young people and middle level professionals are keen to work for a new venture at substantially reduced remuneration, as it offers more scope for entrepreneurship and job satisfaction than the established companies. There is also a pride of achievement if their efforts contribute to its fruition.
Intellectual challenges aside, it is a common practice for start-ups to offer generous share options to employees in order to attract the right talent into their folds. This is a powerful incentive to motivate the staff to do their utmost and to share in the company’s prosperity if it reaches its goal Many regard this as the foundation of a successful enterprise.
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