The general circulation of the surface water in Mediterranean is ______．A.counter-clockwiseB.clockwiseC.from east to westD.from north to south
The general circulation of the surface water in Mediterranean is ______．
A.counter-clockwise
B.clockwise
C.from east to west
D.from north to south
相关考题：
It can be learned from the passage that about four billion years ago ______.A. the earth was in molten stateB. the earth surface temperature was above 100℃C. the earth surface temperature was below 100℃D. rain water could remain on the earth
The distance between the surface of the water and the tidal datum is the______．A.height of tideB.charted depthC.actual water depthD.range of tide
Indirect cooling of fuel injector nozzle holders for diesel engines is accomplished primarily byA.heat conduction into the injected fuel oilB.heat conduction into the water jacket wallC.water circulation through passages in the holderD.fuel oil circulation through passages m the holder
共用题干第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.The word"fraction"in the second paragraph means________.A:a large areaB:a very small amountC:an important systemD:a major source of information
共用题干第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.Most of the fresh water on Earth________.A:is in the form of ice at the poles and on mountainsB:is stored undergroundC:is found in rivers and lakesD:comes from the rain
共用题干第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.Liquid water only exists________.A: in the center of the earthB:on the surface of our planetC:in the coastal areas of the earthD:in a very narrow range of temperatures
共用题干第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.There is more of rainfall________.A:over the mountains than over the riversB:over the rivers than over the mountainsC:over the land than over the oceansD:over the oceans than over the land
单选题A(n) （） is a mechanical attack on the metal surface which may be due to a disturbance in the flow of the water over the blade of the propeller.AerosionBcorrosionCpittingDdezincification
单选题A shallow dish positioned at the normal water level is connected to the（）This enables the blowing down or removal of scum and impurities from the water surface.Amain stern stop valveBauxiliary steam stop valveCscum valveDblow down valve
单选题Which of the following statements concerning the water tube and fire tube boilers is not true?（）Anatural circulation of the water in the water tube boiler is better than that in the fire tube boilerBfor the same output the water tube boiler will carry less mass of water compared with the fire tube boilerCthe water tube boiler will cost shorter time for steam raisingDthe water tube boiler require lower skill in operating and maintaining
单选题For the proper control of the air temperature in an air conditioning system using chilled water circulation, which of the listed conditions should remain constant regardless of load changes?（）AChilled water system supply temperatureBChilled water system return temperatureCCompressor discharge temperatureDCompressor suction pressure
单选题Bottom blow valves are installed on auxiliary water-tube boilers to （）Aremove suspended and precipitated solids from the boiler waterBcompletely drain the boiler in an emergency situationCprevent hardened scale deposits in the water drumDremove floating impurities from the oily water surface
单选题Large pipes or （） are fitted between the steam and water drums to ensure good natural circulation of water.Afire-tubesBfurnacesCdown-comersDsoot-blowers
单选题If you swim in a river or lake, be sure to investigate________is below the water surface. Often there are rocks or branches hidden in the water.AwhatBwhoCthatDwhoever
单选题The distance between the surface of the water and the tidal datum is the （）.Arange of tideBheight of tideCcharted depthDactual water depth
单选题Indirect cooling of fuel injector nozzle holders for diesel engines is accomplished primarily by （）.Aheat conduction into the injected fuel oilBheat conduction into the water jacket wallCwater circulation through passages in the holderDfuel oil circulation through passages in the holder
单选题_____ most of the earth's surface is covered by water, fresh water is very rare and precious.AAsBOnceCIfDAlthough
单选题Impurities from the boiler water surface can be removed through the （）.Asafety valveBblow down valveCscum valveDfeed check valve
单选题The waterplane area is described as the intersection of the surface of the water in which a vessel floats and the（）.AbaselineBvertical reference planeChullDhorizontal reference plane
单选题In a general oil cooler circulated by sea water, the oil is at a higher pressure, the result being that any leak in the cooler will mean a loss of （）.AoilBsea waterCairDfresh water
单选题Shaker, circulation and spray are the three general methods used in（）Apre-injection fuel oil treatmentBlube oil filtrationClube oil purificationDpiston cooling
单选题One of the causes of ocean currents is density differences in the water. This is true because （）.Ain an area of high density the water's surface is lower than in an area of low densityBsurface water flows from an area of high density to one of low densityCthe lesser the density gradient the freer the water is to moveDit is the density differences that cause the currents to stay in the troughs
单选题According to the passage, which of the following factors might spoil the tourists' fun at Mediterranean resorts and beaches？APolluted water.BCrowded buses.CTraffic jams.DRainy weather.
单选题Large pipes or down-comers are fitted between the steam drum and （） to ensure good natural circulation of water.Afire-tubesBfurnacesCwater drumsDwater wall tubes
单选题Considering the general circulation of the atmosphere，the wind system between latitudes 30°N and 60°N is commonly called the（）.Aprevailing westerliesBhorse latitudesCtrade windsDsubpolar low pressure belts