In the Time apportionment base cost formula, where all expenditure was incurred before valuation date, variables P, B, N and T can be correctly described as: A. P= Proceeds, B= Expenditure after 1 Oct '01, N= Years from 1 Oct '01 to disposal, T= Years from acquisition to 1 Oct '01 B. P= Purchase price, B= Expenditure before 1 Oct '01, N= Years from 1 Oct '01 to disposal, T= Years from acquisition to 1 Oct '01 C. P= Purchase price, B= Expenditure after 1 Oct '01, N= Years from 1 Oct '01 to disposal, T= Years from acquisition to 1 Oct '01 D. P= Proceeds, B= Expenditure before 1 Oct '01, N= Years from acquisition to 1 Oct '01, T= Years from 1 Oct '01 to disposal.