Permanent magnetism is caused by（）.

A . If the quadrantal spheres are out as far as possible replace them with smaller spheres B . If the quadrantal spheres are in as far as possible remove one of the spheres C . If the quadrantal spheres are in as far as possible replace them with smaller spheres D . If the quadrantal spheres are out as far as possible，move the quadrantal spheres i

A . An agonic line B . The magnetic equator C . A magnetic meridian D . All of the above

A . variation B . deviation C . compass error D . drift

A . fore-and-aft and athwartships magnets B . dip needle and heeling magnet C . heeling magnet and Flinders bar D . Flinders bar and quadrantal sphere

A . Quadrantal spheres B . Heeling magnets C . Athwartships magnets D . Fore-and-aft magnet

A . geographic pole and the magnetic pole B . lubber's line and true north C . horizontal and the magnetic line of force D . compass heading and the magnetic heading

A . zero B . equal to variation C . eliminated by adjusting the compass D . constant at any geographical locatio

A . It requires anchor handling boats with more horsepower B . Chain chasers work in shallow water only C . Chain chasers will not work with piggyback anchors D . It takes longer to deploy anchors using chain chaser

A . Move the quadrantal spheres closer to the compass B . Raise the heeling magnet if the red end is up C . Remove some of the Flinders bar D . Raise or lower the athwartship magnet

A . removed from the anchor chain B . connected to a buoy at the anchor C . stripped back to the rig and secured D . connected to a buoy halfway down the chai

A . clean anchor chain as it's hauled in B . recover anchors which have lost their buoys C . run and retrieve anchors D . prepare anchor chain for inspectio

A . increases B . remains the same C . decreases D . is unimportant and may be neglected

A . will add to B . will subtract from C . may add to or subtract from D . will not change

A . hammering and jarring B . vibration and pounding C . varying magnetic fields D . stable or permanent magnetism of the shi

A . Flinders bar B . Soft iron spheres C . Fore-and-aft permanent magnets in their trays D . Heeling magnet

A . They are not subject to permanent magnetism; no check is necessary B . Semiannually C . Annually D . Every five year

A . Along the magnetic equator B . Connected by the isoclinal line C . The isopors D . The magnetic pole

A . Compass error and variation are equal B . Compass north will be true north C . Variation will equal deviation D . There will be no compass error

A . the lines of force cross the equator on a 0°-180°alignment B . the quadrantal error is 0° C . there is no vertical component of the Earth's magnetic field D . the intercardinal headings have less than 1&deg

A . Magnetic materials of the same polarity repel each other and those of opposite polarity attract B . The Earth's magnetic lines of force are parallel to the surface of the Earth C . Magnetic meridians connect points of equal magnetic variation D . The compass needle(s) will，when properly compensated，lie parallel to the isogonic lines of the Earth

A . It compensates for the error caused by the vertical component of the Earth's magnetic field B . It compensates for error caused by the heeling of a vessel C . It compensates for quadrantal deviation D . It is only needed in equatorial water

A . being moored for a long time on one heading B . being struck by lighting C . steaming from the north magnetic hemisphere to the south magnetic hemisphere D . loading a homogenous magnetic cargo such as steel plate，iron bars，etc

A . opposite polarity B . the same polarity C . negative polarity D . positive polarity

A . hard iron B . soft iron C . vertical iron only D . horizontal iron only