....................... is the non-fusion method of joining dissimilar metals with metals whose melting temp is greater than $${400^ \circ }C$$.

In spot welding of aluminium sheets, the welding current should be .........A........ and weld time should be kept ............B......... than for $$MS$$ sheet of same thickness.

(A). higher / lower, (B). higher / lower

The mode of metal transfer in $$C{O_2}$$-$$MIG$$ welding at low temperature is