In the consumable electrode shielded metal arc welding process, which of the following observations are correct?
P. The, weld composition does not depend upon the basicity of the slag.
Q. Basic flux is used to achieve low hydrogen content-and low inclusion content in the weld metal.
R. Reverse polarity of the direct current power source is used to weld thin sheets.
S. Coated electrodes are classified by tensile strength of the weld metal deposit.