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问题 单项选择题

矿井井筒提升和斜井运输中的动力设备是提升电动机，按其所带滚筒的直径分，大于（）米的称为提升机，小于（）米的称为提升小绞车。

A、1，1

B、2，2

C、1，2

D、2，1

答案

参考答案：B

阅读理解

Are you aged between 14 and 19 years old? Do you care about the environment around you? Would you please help make the area you live in cleaner and safer?

If your answers are “yes”, “yes” and “yes”, then read on! You may be surprised to hear that you can actually (事实上) get money for improving your community (社区).

The “Big Lottery” is giving money to groups of teenagers who want to become active citizens(公民). We have ￡80,000 to give away. We’re looking for young people to take part in schemes (规划) and projects near to the places they live in.

Here are some easy things you could do to get started:

Meeting the neighbors

Everybody needs good neighbors. Knock on people’s doors and find out what they need to improve in your areas. Set a date for a meeting and then make some plans together. If you don’t want to go around to their houses, you could always put a note through their doors.

Neighborhood watch

Neighborhood watch schemes are very popular in the UK. If you go away on holiday and leave your house, it’s very nice to know that a neighbor is keeping an eye on it. You could set one up easily and quickly.

Lending a hand

There are elderly people living in the neighborhood who may not be able to do the things that you can. Offer to do their shopping once a week, look after their gardens or walk their dogs!

No littering

Nobody likes picking up rubbish, but a clean street can make all the difference. Take it in turns to go out once or twice a week and see what you can find. You never know, one day you might find something valuable!

Recycling

Nearly two-thirds of your rubbish can be recycled. Some areas already provide places for people to recycle bottles, tins, plastic and paper. Find out if this is done in your neighborhood. If it is not, do something about it.

So go on…help make your neighborhood “street ahead”. Just tell us what kind of project you want to get involved in. Then we’ll send you more details. Take positive (积极的) action and help make your neighborhood a better place to live in!

小题1:What is the passage mainly about?

A．Why we should care about the elderly people in our community.

B．What we can do to improve the environment of our community.

C．How we can recycle daily rubbish properly in our community.

D．When we should get the neighbors together to meet their needs.小题2:Which of the following is TRUE according to the passage?

A．The writer doesn’t agree to work for the “street ahead”.

B．Teenagers aged from 14 to 19 are not allowed to join in.

C．It is hard to find a neighbor to watch your house in the UK.

D．We will get money if we give any help in our community.小题3:What can you infer from the passage?

A．The center for elderly people will be larger.

B．The writer is a member of the “Big Lottery”.

C．Communities will take the place of schools.

D．The writer is the manager of the community.
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单项选择题

The city water pipes in Rome were usually of baked clay or lead; copper was sometimes used and also hollowed stone. For the large supply conduits leading to the city the Romans used covered channels with free water surfaces, rather than pipes. Perhaps this choice was a matter of economics, for apparently they could make lead pipes up to 15 inches in diameter. While pipes can follow the profile of undulating ground, with the pressure increasing in the lower areas, channels cannot. They must slope continuously downwards, because water in channels does not normally flow uphill; and the grade must be flat, from 1 in 60 in small channels to perhaps 1 in 3,000 in large ones, to keep the water speed down to a few feet per second. Thus the main supply channels or aqueducts had long lengths of flat grade and where they crossed depressions or valleys they were carried on elevated stone bridges in the form of tiered arches. At the beginning of the Christian era there were over 30 miles of these raised aqueducts in the 250 miles of channels and tunnels bringing water to Rome. The channels were up to 6 feet wide and 5 to 8 feet high. Sometimes channels were later added on the tops of existing ones. The remains of some of these aqueducts still grace the skyline on the outskirts of Rome and elsewhere in Europe similar ruins are found.

Brick and stone drains were constructed in various parts of Rome. The oldest existing one is the Cloaca Maxima which follows the course of an old stream. It dates back at least to the third century B.C. Later the drains were used for sewage, flushed by water from the public baths and fountains, as well as street storm run-off.

The truly surprising aspect of the achievements of all the ancient hydraulic artisans is the lack of theoretical knowledge behind their designs. Apart from the hydrostatics of Archimedes, there was no sound understanding of the most elementary principles of fluid behaviour. Sextus Frontinus, Rome’s water commissioner around A.D. 100, did not fully realize that in order to calculate the volume rate of flow in a channel it is necessary to allow for the speed of the flow as well as the area of cross-section. The Romans’ flow standard was the rate at which water would flow through a bronze pipe roughly 4/3 inch in diameter and 9 inches long. When this pipe was connected to the side of a water-supply pipe or channel as a delivery outlet, it was assumed that the outflow was at the standard rate. In fact, the amount of water delivered depended not only on the cross-sectional area of the outlet pipe but also on the speed of water flowing through it and this speed depended on the pressure in the supply pipe.

In order to calculate the volume of water flowing through a pipe, it is important to know its speed and（）

A．the area across the end of the pipe

B．the length of the pipe

C．the water pressure in the pipe

D．the level from which the water falls
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