A stainless steel weld has a crack open to the surface. Which NDT method will reveal it most effectively?

For alterations or repairs on vessels that were previously post-weld heat treated as a code requirement and fabricated of P-1 and P-3 materials, preheating is not to be less than ___________ may be considered as an alternative to PWHT.

In certain MT Check of pressure Vessel, The size of "indication" for a certain discontinuity was seen as 4 mm but after the MP Check and using magnifying glass it was seen having actual size as 2.5mm only. If stipulated acceptance criterion for that type of discontinuity was 3 mm, your decision is:

PT examination is used to detect the surface cracks in welds as well as in base metal plates. For proper detection,

Determine in what two ways may the probable corrosion rate for a new vessel be determined before the first internal inspection?