什么是选择成本（Alternative cost)？

A.为谁生产

B.生产什么.

C.如何生产

D.生产多少

a.在该宿舍内，播放电影是一种公共物品吗？为什么？

b.如果租一部电影的花费为8美元，为使室友的总剩余最大化，应该租几部电影？

c.如果他们从b中得出了所选择的最适数量，并平等地分摊租电影的费用，每个人从看电影中得到了多少剩余？

d.有一种分摊成本的方法能保证每个人都获益吗？这种解决方法引起了什么实际问题？

e.假设他们事前一致同意选择有效数量并平均分摊录像带的成本。当问到Judd的支付意愿时，他有说实话的激励吗？如果有的话，为什么？如果没有的话，他最可能说什么？

f.关于公共物品的最适供给量这个例子告诉了我们什么？

A.在降低风险的成本与收益的权衡过程中，厌恶风险的人们在相同的成本下更倾向于做出低风险的选择

B.是指投资者不关心风险，当资产的期望损益以无风险利率进行折现时，他们对风险资产和无风险资产同样偏好

C.通常主动追求风险，喜欢收益的动荡胜于喜欢收益的

D.它可以用来测量人们为降低所面临的风险而进行支付的意愿

A.最关键的是省钱——同等带宽情况下，SD-WAN相较传统MPLS电路，每年至少可为企业节省30%的成本投入

B.部署简单，秒速完成——设备上电后自动获取配置，零接触部署，差不多就是即插即用，不用进行物理施工

C.接口通吃，负载均衡——支持MPLS、SDL、PON光纤、4G LTE，甚至5G等多种连接类型

D.自主选择最佳路由——连接不同的分部，SD-WAN可以根据现网情况和配置策略，自主选择最佳路径，确保最低时延

E.自管自控，智能运维——管理平台图形可视化，管理员通过网管界面能看到整个网络运行情况

F.无需互联网专线接入

从供选择的答案中选出应填入下面一段英文中______内的正确答案。

Java was introduced by Sun Microsystems in 1995 and instantly(1)created a new sense of the interactive possibilities ofthe Web. Both ofthe major Web browsers include a Java(2)virtual machine. Almost all major operating system developers (IBM, Microsoft, and others) have added Java(3)compilers as part oftheir product offerings.

The Java virtual machine includes an optional just-in-time compiler that(4)dynamically compiles bytecode into executable code as an alternative to(5)interpreting one bytecode instruction at a time. In many(6)cases, the dynamic JIT compilation is faster than the virtual machine interpretation.

JavaScript should not be(7)confused with Java. JavaScript, which originated at Netscape, is interpreted at a higher level, is easier to learn than Java, but(8)lacks some of the portability of Java and the speed of bytecode. Because Java applets will run on almost any operating system without(8)requiring recompilation and because Java has no operating system-unique extensions or variations, Java is generally regarded as the most strategic(10)language in which to develop applications for the Web.

供选择的答案：

1．confused 2．compilers 3．dynamically 4．requiring 5．cases

6．interpreting 7．language 8．virtual 9．created 10．lacks

A.impact

B.academic

C.insult

D.alternative

 checks, which provide a secure ____to carrying your money in cash.A. substitute      B. preference       C. selection       D. alternative

A、ignoring details

B、over-generalizing

C、imposing consistency

D、preconnecting causes and effects

What are the man and the woman mainly discussing？

A．An alternative use of fuel oil.

B．A way to make fuel oil less polluting.

C．A new method for locating underground oil.

D．A new source of fuel oil.