(a) Any reference in this Part to the sale of any property includes a reference to the sale of that property together with any other property and, where property is sold together with other property, so much of the net proceeds of the sale of the whole property as on a just apportionment is properly attributable to the first-mentioned property shall for the purposes of this Part be deemed to be the net proceeds of the sale of the first-mentioned property, and references to expenditure incurred on the provision or the purchase of property shall be construed accordingly.
(b) For the purposes of this subsection, all the property which is sold in pursuance of one bargain shall be deemed to be sold together, notwithstanding that separate prices are, or purport to be, agreed for separate items of that property or that there are, or purport to be, separate sales of separate items of that property.
(2) Subsection (1) shall, with the necessary modifications, apply in relation to other sale,
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