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单选题
Small floes of rough，hummocky sea ice capable of damaging a vessel（）.
A
can usually be detected by radar in a smooth sea at a range of 4 to 6 kilometers
B
are indistinguishable from sea return on the PPI
C
are invisible to radar when covered with a thick layer of snow
D
are usually seen at night before they are close enough to provide a radar echo
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更多 “单选题Small floes of rough，hummocky sea ice capable of damaging a vessel（）.A can usually be detected by radar in a smooth sea at a range of 4 to 6 kilometersB are indistinguishable from sea return on the PPIC are invisible to radar when covered with a thick layer of snowD are usually seen at night before they are close enough to provide a radar echo” 相关考题
考题
Over the past decades, sea ice ____ in the Arctic (北极) as a result of global warming.
A had decreasedB will decreaseC has been decreasingD is decresing
考题
________ causes strong winds and rough sea at northwest Bay of Biscay．A.Strong low pressureB.Strong high pressureC.Steep pressure gradientD.Steep gradient pressure
考题
The 3-cm radar as compared to a 10-cm radar with similar specifications will ______.A.give better range performance in rain，hail，etcB.display small targets in a mass of dense sea clutter at a greater rangeC.have less sea return in choppy rough seasD.display a more maplike presentation for inshore navigation
考题
Biodegradation of the oil slick in sea water is assisted by all the following marine micro-organisms which are capable of metabolising oil compounds except ______A.bacteriaB.mouldsC.yeastsD.seals
考题
When weighing anchor in a rough sea，how would you avoid risk of damaging the bow plating ________．A.Heave it home as fast as you canB.Heave it home intermittently，between swellsC.Leave the anchor under foot，until the vessel may be brought before the seaD.Wait for a calm spot between seas，then house it
考题
When operating in an area where sea ice and icebergs are present，which statement is TRUE ________．A.Icebergs may travel in a direction many degrees different from the sea iceB.Both icebergs and sea ice will move in approximately the same direction and at the same speedC.Icebergs and sea ice will move in the same direction，but at different speeds due to the sail effect of the bergD.Icebergs and sea ice will move in the same direction，but the iceberg will move slower because of its underwater bulk
考题
You are heading into the sea during rough weather．Having too much weight forward can cause your small boat to ______．A.BroachB.Plunge into the waveC.Rise rapidly over the waveD.List
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
考题
资料：A high-precision NASA radar instrument left a NASA airport in Southern California for Iceland on January 28 to create detailed maps of how glaciers move in the dead of winter. This will help scientists around the world better understand some of the most basic processes involved in melting glaciers, which are major contributors to rising sea levels.
NASA used the same airborne instrument in June 2012 to map the summer flows of two Icelandic ice caps. The ice caps — large areas of permanent snow and ice cover — encompass multiple glaciers flowing in different directions and at different speeds. By mapping the same ice caps now, in winter, when the surface remains frozen all day, and then comparing the winter and summer velocities, the researchers will be able to isolate the effects of melt water.
Above is a view of a small part of the Hofsjkull ice cap, which encompasses several glaciers. The fan at upper left is part of a glacier called Mlaj?kull.
For more on the research, see this NASA press release.
What is the mission of the NASA radar instrument?A.To investigate the climate change.
B.To make maps about moving glaciers.
C.To measure the rising sea levels.
D.To slow the melting process of glaciers
考题
—The sea is very rough today.
—Yes，I‘ve never seen_______before.A.such rough sea
B.such a rough sea
C.so rough sea
D.that rough sea
考题
从每小题的四个选择项中，选出最佳的一项，并把它前面的大写字母填入左边的括弧里。
—The sea is very rough today．
—Yes，I‘ve never seen_______before．A.such rough sea
B.such a rough sea
C.so rough sea
D.that rough sea
考题
单选题Multi-year ice is the hardest sea ice and should be avoided if possible. It is recognizable because of what tone to its surface color? （）A
GreenishB
BluishC
GreyD
Grey-white
考题
单选题There is a possibility that small vessel，ice and other floating objects may not be（）by radar at an adequate range.A
reflectB
shownC
detectedD
defected
考题
单选题The 10-cm radar as compared to a 3-cm radar of similar specifications will（）.A
be more suitable for river and harbor navigationB
provide better range performance on low lying targets during good weather and calm seasC
have a wider horizontal beam widthD
have more sea return during rough sea conditions
考题
单选题You are transporting dangerous cargo on your vessel．You must inspect this cargo（）.A
DailyB
Daily，at sea onlyC
After encountering rough weatherD
After loading and prior to arrival in port only
考题
单选题When operating in an area where sea ice and icebergs are present，which statement is TRUE? （）A
Icebergs may travel in a direction many degrees different from the sea iceB
Both icebergs and sea ice will move in approximately the same direction and at the same speedC
Icebergs and sea ice will move in the same direction，but at different speeds due to the sail effect of the bergD
Icebergs and sea ice will move in the same direction，but the iceberg will move slower because of its underwater bulk
考题
单选题A fully loaded motor-propelled lifeboat must be capable of attaining a speed of at least（）.A
3 knots in smooth waterB
6 knots in smooth waterC
3 knots in rough waterD
6 knots in rough water
考题
单选题（）causing strong winds and rough sea north west Bay of Biscay.A
Strong low pressureB
Strong high pressureC
Steep pressure gradientD
Steep gradient pressure
考题
单选题When ship navigating in rough sea, the first measure taken by the chief engineer to prevent the overload should be（）A
cleaning fuel oil, lubricating oil and seawater filterB
reducing fuel feeding of the main engine appropriately or reducing the pitch angle of propellerC
using low sea chestD
closing the skylight and the ventilation opening, which doesn’t affect the normal work of equipments
考题
单选题The 3-cm radar as compared to a 10-cm radar with similar specifications will（）.A
give better range performance in rain，hail，etcB
display small targets in a mass of dense sea clutter at a greater rangeC
have less sea return in choppy rough seasD
display a more map like presentation for inshore navigation
考题
单选题When anchoring a small sailing vessel in rough weather，the best anchor line would be composed of（）.A
chain-wireB
chain-manilaC
chain-nylonD
all chain
考题
单选题Do you think such a small company will be capable of ______ this large order?A
handlingB
handledC
to handleD
handle
考题
单选题Over the past decades, sea ice _____ in the Arctic(北极) as a result of global warming.A
had decreasedB
will decreaseC
has been decreasingD
is decreasing
考题
单选题Biodegradation of the oil slick in sea water is assisted by all the following marine micro-organisms which are capable of metabolising oil compounds except（）.A
bacteriaB
mouldsC
yeastsD
seals
考题
单选题Where do polar bears usually hunt seals?A
On land.B
In open water.C
In openings in the sea ice.D
At the bottom of the sea.
考题
单选题When ship navigating in rough sea, the correct operation is （）A
navigating with a low diesel engine speedB
navigating with a stable diesel engine speedC
increasing the efficiency of propellerD
increasing fuel injection
考题
单选题When weighing anchor in a rough sea，how would you avoid risk of damaging the bow plating （）.A
Heave it home as fast as you canB
Heave it home intermittently，between swellsC
Leave the anchor under foot，until the vessel may be brought before the SeaD
Wait for a calm spot between seas，then house it
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