The consumption of an oxy-acetylene flame for cutting of steel contains more oxygen

The composition of an oxy-acetylene flame for cutting of steel contain more oxygen.

The type of coated electrode most widely used for welding low carbon steel is

Filler material is ......... A...... in resistance welding and the heat generated in the process is directly proportional to ........ B.........

(A). used / not used$$\,\,\,\,\,\,\,\,\,$$ $$\,\,\,\,\,\,\,\,\,$$ (B). square of the current / cube of the current