A liquid of density 1.742 g cm-3 is observed to show a capillary rise of 7.3 mm in a tube of radius 0.65 mm. Then the surface tension of the liquid is
4.1 `xx` 10-2 dynes cm-1
4.1 `xx` 103 dynes cm-1
7.1 `xx` 10-3 dynes cm-1
None of these
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