单选题Officers use sextants to observe （）.AstarsBcelestial bodiesCthe sunDthe moon
单选题
Officers use sextants to observe （）.
A
stars
B
celestial bodies
C
the sun
D
the moon
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When observe , you use a part of your body as the tool. () A. temperatureB. pulseC. blood pressureD. respiration
Text 2 To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, they do indeed give the impression of being affixed to the inner surface of a great hollow sphere surrounding the earth. Ancient people, in fact, literally believed in the existence of such a celestial sphere. As the earth spins on its axis, the celestial sphere appears to turn about us each day, pivoting at points on a line with the earth's axis of rotation. This daily turning of the sphere carries the stars around the sky, causing most of them to rise and set, but they, and constellations they define, maintains fixed patterns on the sphere, just as the continent of Australian maintains its shape on a spinning globe of the earth. Thus the stars were called fixed stars.The motion of the sun along the ecliptic is, of course, merely a reflection of the revolution of the earth around the sun, but the ancients believed the earth was fixed and the sun had an independent motion of its own, eastward among the stars. The glare of sunlight hides the stars in daytime, but the ancients were aware that the stars were up there even at night, and the slow eastward motion of the sun around the sky, at the rate of about thirty degrees each month, caused different stars to be visible at night at different times of the year.The moon, revolving around the earth each month, also has an independent motion in the sky. The moon, however, changes its position relatively rapidly. Although it appears to rise and set each day, as does nearly everything else in the sky, we can see the moon changing position during as short an interval as an hour or so. The moon's path around the earth lies nearly in the same plane as the earth's path around the sun, so the moon is never seen very far from the ecliptic in the sky. There are five other objects visible to the naked eye that also appear to move in respect to the fixed background of stars on the celestial sphere. These are the planets Mercury, Venus, Mars, Jupiter, and the Saturn. All of them revolve around the sun in nearly the same plane as the earth does, so they, like the moon, always appear near the ecliptic. Because we see the planets from the moving earth, however, they behave in a complicated way, with their apparent motions on the celestial sphere reflection both their own independent motions around the sun and our motion as well.第26题：The ancient people believed that ________.[A] the earth was spinning on the axis of the sky[B] the sky was a hollow sphere spinning around the earth[C] the patterns of stars on the sky would never change[D] the stars around the sky were not stationary
Which of the following is true about the motion of the moon?[A] The moon and the sun are moving in the same plane.[B] The moon revolved along the ecliptic.[C] The moon moves faster than the sun.[D] The position of the moon can be found changed in an hour's time.
A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?A.The motion of the apparent sun is along the eclipticB.Measurement of time is along the celestial equatorC.The speed of the Earth's revolution is not constantD.There are variations in the Earth's rotational speed
Where a one-berth cabin is provided solely for the accommodation of a pilot，the existence of such a room，although not itself eligible for deduction，shall not cause the disallowance of the officers’ mess-room，bathroom，W．C．，etc．，as would be the case if the rooms were intended for the use of a passenger．This sentence indicates that ______.A.a one-berth cabin for a pilot is deductibleB.the officers’ mess-room，bathroom，W．C．，etc．，which are also used by a passenger，is deductible．C.the officers’mess-room，bathroom，W．C．，etc．，which are also used by a pilot，is deductibleD.a one-berth cabin for a passenger is deductible
A time diagram is a diagram of the celestial sphere as observed from above the ______.A.south celestial poleB.north celestial poleC.observer's meridianD.Greenwich meridian
A time diagram is a diagram on the plane of the ______.A.celestial meridianB.celestial equatorC.celestial horizonD.principal vertical circle
The use of the expression “I won't bore you with .all the detail ...” includes that people usually observe the（ ）maxim in their daily conversations.A.QuantityB.QualityC.RelevanceD.Manner
若想连接字符串"Zang"，"Zoom"和"Moon"，可使用哪种形式（）A、"bang"，"Zoom"，"Moon"B、"bangZoomMoon"C、"bang""Zoom""Moon"D、"bang"+"Zoom"+"Moon"
单选题You observe that the senior database administrator always uses the following command when connecting to Recovery Manager （RMAN）， and then starts executing commands to backup the database files： $ rman target / What would be the effect of this command？（）ARMAN would use the current operating system location to place the backup.BRMAN would use the control file of the target database to maintain the backup.CRMAN would use the recovery catalog of the target database to maintain the backup.DRMAN would use the control file of the target database to maintain the backup metadata. ERMAN would use the recovery catalog of the target database to maintain the backup metadata.
单选题You observe that the senior database administrator always uses the following command when connecting to Recovery Manager （RMAN）， and then starts executing commands to backup the database files： % rman target / What would be the effect of this command？（）A RMAN would use the current operating system location to place the backup.B RMAN would use the control file of the target database to maintain the backup.C RMAN would use the recovery catalog of the target database to maintain the backup.D RMAN would use the control file of the target database to maintain the backup metadata.E RMAN would use the recovery catalog of the target database to maintain the backup metadata.
单选题It is difficult to determine which limb of the Moon is fully illuminated（）.Awhen the Moon is low in the sky at rising or settingBat the new Moon phaseCwhen taking Moon sights during daylightDwhen the terminator is nearly vertical
单选题The equator is（）.Athe primary great circle of the Earth perpendicular to the axisBthe line to which all celestial observations are reducedCthe line from which a celestial body's altitude is measuredDAll of the above
单选题Apparent time is based on（）.Aa fictitious sun moving along the celestial equatorBthe visible sun moving along the eclipticCthe Moon's motion in relation to the SunDthe movement of the first point of Aries
单选题A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?（）AThe motion of the apparent sun is along the eclipticBMeasurement of time is along the celestial equatorCThe speed of the Earth's revolution is not constantDThere are variations in the Earth's rotational speed
单选题The use of the expression I won't bore you with all the detail..…includes that people usually observe the _________ maxim in their daily conversations.AQuantityBQualityCRelevanceDManner
单选题Aphelion is the point where the Sun（）.Aand Moon and Earth form a right angleBand Moon and Earth are in lineCcrosses the celestial equatorDis farthest from the Earth
单选题Concerning a celestial observation，the azimuth angle is measured from the principal vertical circle to the（）.AGreenwich celestial meridianBhour circle of the bodyClocal celestial meridianDvertical circle of the body
单选题The simplest method to use for determining if a centrifugal pump is operating as designed, is to （）.Aclosely observe the pump discharge temperatureBclose off the discharge valve, and watch for a rise in pressureCmomentarily close off the suction valve, and watch for a rise in pressureDuse a clamp on ammeter and compare the readings to past records
单选题A time diagram is a diagram of the celestial sphere as observed from above the（）.Asouth celestial poleBnorth celestial poleCobserver's meridianDGreenwich meridian
单选题Spring tides occur（）.Awhen the moon is new or fullBwhen the moon and sun have declination of the same nameConly when the moon and sun are on the same sides of the earthDat the beginning of spring when the sun is over the equator