常用于高压管线连接的是（）。A、平焊法兰 B、对焊法兰 C、螺纹法兰 D、活套法兰

阅读理解。

     Some people think that they have an answer to the problems of automobile crowding and pollution in large

cities. Their answer is the bicycle, or bike.

     In a great many cities, hundreds of people ride bicycles to work every day. In New York City, some bike

riders have even formed a group called "Bike for a Better City". They claim that if more people rode bicycles

to work there would be fewer automobiles in the downtown section of the city and therefore less dirty air

from car engines.

     For several years this group has been trying to get the city government to help bicycle riders. For example,

they want the city to paint special lanes-for bicycles only-on some of the main streets, because when bicycle

riders must use the same lanes as cars, there may be accidents. "Bike for Better City" feels that if there were

special lanes, more people would use bikes.

     But no bicycle lanes have been painted yet. Not everyone thinks it is a good idea. Taxi drivers don't like the

idea-they say it will slow traffic. Some store owners on the main streets don't like the idea-they say that if there

is less traffic, they will have less business. And most people live too far from downtown to travel by bike.

     The city government has not yet decided what to do. It wants to keep everyone happy. On weekends,

Central Park-the largest open place in New York-is closed to cars, and the roads may be used by bicycles only.

But "Bike for a Better City" says that this is not enough and keeps fighting to get bicycle lanes downtown. Until

that happens, the safest place to bicycles may be in the park.

1. The underlined word"automobiles" in the second paragraph means _____.

A. trains

B. cars

C. planes

D. ships

2. Which of the following is TRUE according to the passage?

A. Special lanes are needed on every street.

B. The Central Park is closed to cars on weekdays.

C. "Bike for a Better City" members ride bicycles to work.

D. Accidents won't happen if cars and bikes are on different lanes. 

3. No bicycle lanes have been painted yet because _____.

A. the idea hasn't been accepted by all

B. the main streets are not wide enough

C. the city government can't help to paint the lanes

D. there's no need for most people to travel by bike

4. This passage is mainly about _____.

A. city problems and "Bike for a Better City"

B. "Bike for a Better City" and the city government

C. the government's idea on traffic and city pollution

D. a suggestion on the city problems of traffic and pollution

食物脂肪消化吸收后进入血液的主要方式是（）。

A.甘油及FA

B.DG及FA

C.MG及FA

D.CM

E.TG

绩效管理体系的要素有（）

A、考核目的

B、考核方法

C、评分标准与方式

D、考核的时间与频率

E、考核结果的使用方式

根据JB4708—92《钢制压力容器焊接工艺评定》的规定，板材组合焊缝试件两端应弃去（）。

A．10mm

B．15mm

C．20mm

D．25mm

Small, Imperfectly Formed

One has to look a long time for an American politician of any political stripe who has failed to laud small businesses. Still, many have little clue as to what makes such businesses succeed or fail.
Federal agencies aimed at helping small business, such as the Small Business Administration and the Minority Business Development Agency, have been around for half a century, yet persistent differences remain between the performance of businesses founded by white, male entrepreneurs and the rest. Blacks are less likely to be self-employed, for example, and when they are their businesses, on average, have lower sales and profits than do their white-or Asian-owned counterparts. If researchers could explain the causes of these differences, policy-makers could (at least in theory) supply small businesses with more useful help.
Two researchers for the Census Bureau’s Centre for Economic Studies, Ron Jarmin and C.J. Krizan, recently published a working paper attempting to understand demographic differences behind small businesses’ success and failure. They concentrated on the years 2002 to 2005, with three databases at their disposal: the Survey of Business Owners, conducted every five years; the Longitudinal Foreign Trade Transaction Database, which includes every US export transaction between 1992 and 2005; and a database co-developed by Mr. Jarmin, which allowed the authors to track whether the owners of the firms in their sample had prior experience being their own bosses. By drawing from on the power of the Census’s data collection efforts, the authors hoped to create a more nuanced picture of business survival.
Some of their findings were not terribly surprising. A firm’s chances of survival, regardless of the race or sex of its owner, decreased in poorer areas; and the better the education of the founder, the more likely it was to succeed. Businesses owned by Asians, Hispanics, or Pacific Islanders were more likely to be exporters. Older entrepreneurs were more likely to use personal savings to start their businesses; younger owners were more likely to have to close up shop during the study period than were their middle-aged rivals.
However, the data also confirmed that black-and female-owned businesses tended to perform worse than the average. They were also less likely to have been funded by bank loans. Still, the businesses that survived, regardless of the owner’s race, tended to add employees at similar rates. Furthermore, after controlling for factors such as the education and race of the owner, there was no statistically significant difference in firms’ abilities to expand into different locations. Finally, black entrepreneurs were more likely to have a history of self-employment than their white counterparts. Messrs Jarmin and Krizan’s paper is not the first to suggest that black entrepreneurs, less likely to have other business owners in their family or personal networks, tend to "start small" when they venture out on their own.
Most researchers get to end their papers by speculating, usually without much fear of consequence, as to the policy implications of their work. The authors of this paper, not wishing to imply that the Census Bureau might have policy opinions, declined to do so. But the reader can make some guesses. One is that mentorship programmes may be particularly useful for promoting entrepreneurship among blacks. Another is that reaching out to businesses based on the owner’s race might be less useful than supporting businesses in poorer areas. And small businesses of all stripes would be helped by improving that other institution lauded by politicians: America’s education system.

When working on their paper Ron Jarmin and C.J. Krizan ______.
A. built up three databases
B. mainly studied the data of four years
C. interviewed the owners of some small businesses
D. found the Survey of Business Owners especially helpful