“(3)…regulations prescribing the means to be used for ascertaining for any purpose [and ss. (4) says that different regulations may be made 25 for different purposes under this subsection] the strength, weight or volume of any liquor… 7 (3A) Without prejudice to the generality of subsection (3) above, regulations under that subsection may provide that for the purpose of charging duty on any…beer…contained in any bottle or other container, the strength, weight or volume of the liquor in that bottle or 5 other container may be ascertained by reference to any information given on the bottle or other container by mean of a label or otherwise or to any documents relating to the bottle or other container.”