### Instruction:

Extract the cause and effect entities from the following sentence:
However, a commonly used dye-penetrant etchant (a solution of nitric acid and hydrofluoric acid) has been shown to dissolve stringer material in 304L stainless steel

### Assistant:

NOT_RELEVANT: (a solution of nitric acid and hydrofluoric acid)
CAUSE_1: a commonly used dye-penetrant etchant
KEYWORD: has been shown
EFFECT_1: to dissolve stringer material in 304L stainless steel
VARIABLE: stringer material in 304L stainless steel
CONDITION: to dissolve

