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单选题
Safe water buoys may show ONLY（）.
A
flashing red lights
B
flashing green lights
C
white lights
D
yellow lights
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BThe world is not only hungry，it is also thirsty for water． this may seem strange to you，since nearly 75% of the earth is covered with water． But about 97% of this water is sea water．Man can only drink and use the other 3% fresh water that comes from rivers，lakes，under-ground and other places． And we cannot even use all of that，because some of this fresh water has been made dirty．At the moment，this small amount(数量) of fresh water is still enough for us． However，our need for water is getting greater and greater． Only if we take steps to solve this problem now，we can get away from a serious world water shortage later on． The people of the world cannot have an enjoyable life without enough clean water．On one hand we should stop wasting this little water of ours，on the other hand we should find ways to reuse it，but this has not been done widely．Today，in most large cities，water is used only once and it then returns to the sea or runs into underground places．lf we can make it clean again，it can be used once more just as if it were fresh from a spring．But even if large cities reuse its water，we still would not have enough in the future． Where．could we turn to next for water? To the ocean! How can we do to make use of this great a-mount of sea water? We can take the salt from the water to make it fresh．So if we take all these steps，we'll be in no danger of drying up!( )26． Why does the writer say that the world is thirsty for water?A． The amount of fresh water is really very small．B． The people of the world waste too much water．C． The people of the world have to drink a lot of water every day．D． There are too many people in the world needing water．
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When you go shopping and want to buy some clothes，you should think about which kind of clothes you really need and decide how_____money you can _____on them. Then look at the labels that are inside the new clothes. They tell you how to _____the clothes. The label for a shirt may tell you to wash it in warm water. A sweater label may tell you to wash it in cold water. The label on a coat may say “dry clean only” and cleaning in water may _____this coat. If you do _____the directions say on the label, you can keep your clothes looking their best.1.A. muchB. manyC. large2.A. costB. spendC. take3.A. take place ofB. take use ofC. take care of4.A. changeB. replaceC. ruin5.A. asB. byC. for
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All VHF marine band radios operate in the simplex mode，which means that______．A.only one person may talk at a timeB.only two persons may talk at the same timeC.the radio only transmitsD.the radio only receives
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
The purpose of mentioning the Weddell Sea is__________.
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A．to give an example of cold-water salinity
B．to point out the location of deep waters
C．to make a comparison between hot-water salinity and cold-water salinity
D．to show that the water in the Weddell Sea varies in salinity from place to place
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共用题干
New Product Will Save livesDrinking water that looks clean may still contain bugs（虫子）,which can cause illness. A small company called Genera Technologies has produced a testing method in three stages,which shows whether water is safe.The new test shows if water needs chemicals added to it,to destroy anything harmful.It was invented by scientist Dr. Adrian Parton, who started Genera five years ago.He and his employees have developed the test together with a British water company.Andy Headland,Genera's marketing director,recently presented the test at a conference in the USA and forecast good American sales for it.Genera has already sold 11 of its tests at$42,500 a time in the UK and has a further four on order. It expects to sell another 25 tests before the end of March.The company says it is the only test in the UK to be approved by the government.Genera was formed five years ago and until October last year had only five employees; it now employs 14.Mr Headland believes that the company should make around$19 million by the end of the year in the UK alone.Genera has increased the number of its employees recently.A:Right B:Wrong C:Not mentioned
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共用题干
New Product Will Save livesDrinking water that looks clean may still contain bugs（虫子）,which can cause illness. A small company called Genera Technologies has produced a testing method in three stages,which shows whether water is safe.The new test shows if water needs chemicals added to it,to destroy anything harmful.It was invented by scientist Dr. Adrian Parton, who started Genera five years ago.He and his employees have developed the test together with a British water company.Andy Headland,Genera's marketing director,recently presented the test at a conference in the USA and forecast good American sales for it.Genera has already sold 11 of its tests at$42,500 a time in the UK and has a further four on order. It expects to sell another 25 tests before the end of March.The company says it is the only test in the UK to be approved by the government.Genera was formed five years ago and until October last year had only five employees; it now employs 14.Mr Headland believes that the company should make around$19 million by the end of the year in the UK alone.Genera Technologies has developed a method that determines whether water is clean.A:Right B:Wrong C:Not mentioned
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While troubleshooting a network connectivity issue, you suspect that a router may be missing a route, or may be receiving bad routing information to a destination. What command should you issue to view the route that the router will use to reach a given destination?（）A、pingB、traceC、show ip routeD、show interfaceE、show cdp neighbors
考题
Which command allows viewing of only OSPF routes?（）A、show ip ospf routeB、show ip route protocol ospfC、show route protocol ospfD、show ospf table
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Which command will display only direct routes?（）A、show routeB、show route inet.0 directC、show ip route directD、show route protocol direct
考题
单选题Drinking salt water will（）.A
be safe if mixed with fresh waterB
prevent seasicknessC
dehydrate youD
protect against heat cramps
考题
单选题Drinking salt water will （）A
be safe if mixed with fresh waterB
prevent seasicknessC
promote urine excretionD
protect against heat cramps
考题
单选题At 0230 on 13 August，you are at mile 610.5 AHP when you see about a mile ahead lights on the water near the left bank. What might you see when you come abreast of these lights? （）A
Privately maintained buoys at a yacht clubB
Government buoys marking the Hurricane Point dikesC
Barges moored at the Dennis Landing TerminalD
A pipeline discharging dredge spoil
考题
单选题Which statement concerning the collection of fresh water is FALSE?（）A
Fresh water may be obtained from fishB
lifeboat covers or canopies should be washed with rain before drinking water is collectedC
Fresh water may be collected from condensation inside the life-raftD
Freshwater cannot be produced from standing seawater
考题
单选题Wood or steel hatch covers are made（）by tarpaulins.A
watertightB
resistant to waterC
so safe that no water will affect the holdD
so strong that no water will come into the hold
考题
单选题Safe water buoys may show ONLY（）.A
flashing red lightsB
flashing green lightsC
white lightsD
yellow lights
考题
单选题Which statement concerning the operation of radar in fog is TRUE?（）A
Radar ranges are less accurate in fogB
Navigation buoys will always show up on radarC
A sandy beach will show up clearer on radar than a rocky cliffD
Small wooden boats may not show up on radar
考题
单选题The light rhythm of Morse (A) is shown on（）.A
preferred-channel buoysB
starboard- or port-side buoysC
special marksD
safe water buoys
考题
单选题Lighted white and orange buoys must show which color light?（）A
OrangeB
WhiteC
RedD
Alternating yellow and white
考题
问答题The worst pollution threat is concentrated in and near large cities. There the people-made pollutants increasingly surpass the ability of air and water to dilute (冲淡；稀释) the contaminants (污染物) to safe levels. The natural ecological cycle depends on plants, which absorb some pollutants and release oxygen to the air. But near large cities, natural vegetation becomes scarce, and introduced trees, ornamental shrubs and gardens are far from adequate in absorbing motor vehicle and industrial air pollutants. Finally, some pollutants, most notably atomic waste, may continue to contaminate air, land, and water for thousands of years. Therefore, ecocrisis—ecocatastrophe or ecocide—has been for some time one of the major concerns of not only the ecoactivists and environmentalists, but of many scientists of other fields and the government authorities of many countries as well.
考题
单选题Green lights may appear on（）.A
horizontally banded buoysB
vertically striped buoysC
yellow buoysD
spherical buoys
考题
单选题The changes in the channel’s sands and buoys on this coast are（）this chart can not be considered as a safe guide of the channel.A
frequentB
so frequentC
frequent thatD
so frequent that
考题
单选题Buoys which only mark the left or right side of the channel will never exhibit a light with which characteristic? （）A
FlashingB
Quick flashingC
Composite group flashingD
Equal interval (isophase)
考题
单选题Which statement concerning the collection of fresh water is FALSE?（）A
Fresh water may be obtained from fishB
Lifeboat covers or canopies should be washed with rain before drinking water is collectedC
Fresh water may be collected from condensation inside the liferaftD
Seawater should never be consumed
考题
单选题Buoys are marked with reflective material to assist in their detection by searchlight. Which statement is TRUE? （）A
A safe-water buoy will display red and white vertical stripes of reflective materialB
All reflective material is white because it is the most visible at nightC
A special-purpose mark will display either red or green reflective material to agree with its shapeD
A preferred-channel buoy displays either red or green reflective material to agree with the top band of color
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