For the purpose of these Regulations,

(a) cargo shall be charged per tonne or cubic meter as the Commissioner-General considers appropriate;

(b) the volume or cubic measurements of cargo shall be declared to only one decimal place of the tonne or cubic meter respectively; and

(c) where goods of a like kind and forming part of one consignment are contained in packages of equal size and are properly stacked, the rent charge shall be assessed on the cubic contents of the stack.