(10)WHAT ARE THE RATIO TEST, VECTOR GROUP TEST,MAGNATIC CORE BALANCE TESTS,MEASUREMENT OF INSULATION POWER FACTOR,VACUME TESTS & OIL TIGHTNESS TESTS OF A TRANSFORMER & AND HOW IT CAN BE DONE?
Alternatively try an internet search for your answer (which I am assuming is either homework or general interest), alternatively try a search of CR4 as parts of this question have been answered previously on CR4.