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问题 单项选择题

图示杆件结构支座D处的约束反力为（）。

A.A

B.B

C.C

D.D

答案

参考答案：A

解析：

首先考虑CD杆的平衡可判断出D处约束反力方向，其次考虑整个结构的平衡可得约束反力大小。 [点评] 本题主要考察三个力作用下物体的平衡条件以及物体系统的平衡。

单项选择题

As Oil Declines, So does America


More than 100 years ago, America’s first great economic (26) abroad was spearheaded by its giant oil companies, notably John D. Rockefeller’s Standard Oil Company. These companies (27) powerful beachheads in Mexico and Venezuela, and later in parts of Asia, North Africa and, of course, the Middle East. (28) they became ever more dependent on the extraction of oil in distant lands, American foreign policy began to be (29) around acquiring and protecting US oil concessions in major (30) areas.
With World War Ⅱ and the Cold War, oil and US national (31) became thoroughly intertwined. After all, the United States had prevailed over the Axis (32) in significant part because it possessed vast reserves of domestic petroleum, while Germany and Japan lacked them, depriving their forces of vital (33) supplies in the final years of the war. As it happened, though, the United States was using up its domestic (34) so rapidly that, even before World War Ⅱ was over, Washington (35) its attention to finding new overseas sources of crude oil that could be (36) under American control. As a result, Saudi Arabia, Kuwait and a host of other Middle Eastern producers would become key US oil suppliers (37) American military protection.
There can be (38) question that, for a time, American domination of world oil production would prove a potent source of economic and military power. (39) World War Ⅱ, an abundance of cheap US oil spurred the (40) of vast new industries, including civilian air travel, highway construction, a (41) of suburban housing and commerce, mechanized agriculture, and plastics.

A. reorganized B. readopted C. reaffirmedD. reassessed

Abundant oil also underlay the global expansion of the country’s (42) power, as the Pentagon defended the world while becoming one of the planet’s great oil guzzlers. Its global dominion came to (43) on an ever-expanding array of oil-powered ships, planes, tanks and missiles. As long as the Middle East—and especially Saudi Arabia—served essentially as an American gas station and oil (44) a cheap commodity, all this was relatively painless. That is why the use of military force has been a (45) of American foreign policy since 1987.
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问答题

请使用“答题"菜单或使用VC6打开考生文件夹proj1下的工程proj1。此工程包含程序文件main.cpp。程序中位于每个//ERROR************found************下的语句行有错误，请加以更正。更正后程序的输出应该是：
1958年3月23日比2001年11月5日更早
2001年11月5日比1958年3月23日更晚
2001年11月5日与2001年11月5日是同一日期
注意：只能修改每个//ERROR************found************下的那一行，不要改动程序中的其他内容。
//源程序
#include ＜iostream＞
using namespace std;
class Date
int year;
int month;
int day;
public：
//ERROR************found************
Date(int yyyy, int mm, int dd): yyyy(year),mm(month),dd(day)
bool isLaterThan(Date dt) const //当前日期晚于日期dt时返回true
if(year!=dt.year) return year＞dt.year;
if(month!=dt.month) return month＞dt.month;
return day＞dt.day；

bool isEarlyThan(Date dt) const //当前日期早于日期dt时返回true
if(year!=dt.year) return year＜dt.year;
if(month !=dt.month) return month＜dt.month;
//ERROR************found************
return day＞dt.day；

void showDate() const cout＜＜year＜＜"年"＜＜month＜＜"月"＜＜day＜＜"日";
；
//ERROR************found************
void compareDate(Date dt1 Date dt2) const
if(dt1.isLaterThan(dt2))
dt1.showDate();cout＜＜"比";dt2.showDate();cout＜＜"更晚"＜＜endl;

else if(dt1.isEarlyThan(dt2))
dt1.showDate();cout＜＜"比";dt2.showDate();cout＜＜"更早"＜＜endl;

else
dt1.showDate()；cout＜＜"与"；dt2.showDate()；cout＜＜"是同一日期"＜＜endl；


int main()
Date dt1(1958,3,23),dt2(2001,11,5);
compareDate(dt1,dt2);
compareDate(dt2,dt1);
compareDate(dt2,dt2);
return 0：
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