26. Mark the correct set of ferromagnetic substances :
(A) Iron, cobalt and nickel
(B) Iron, copper and lead
(C) Silicon, bismuth and nickel
(D) Aluminium, sodium and copper
27. Practically the burden on a potential transformer is a :
(A) large inductance
(B) small resistance a
(C) small capacitance
(D) large resistance
28. When the Lead acid battery is fully charged :
(A) Anode is converted into Pb
(B) Cathode is converted into PbO2
(C) Specific gravity of H2SO4 rises about 1.28
(D) Both plates become red
29. 
From the above KVA triangle, find the power factor.
(A) 0.80
(B) 0.60
(C) 0.75
(D) 0.71
30. In delta connection line & phase _______ are different and in star connection line phase _____ are same.
(A) currents, currents
(B) currents, voltages
(C) voltages, currents
(D) voltages, voltages