Which of the following is a final and intermediate expenditure? (a) Purchase of furniture by an office firm (b) Expenditure on the uniforms of the staff of the hospital (c) Expenditure on the repair and maintenance of office building (d) Expenditure on the improvement of machinery in a factory OR Calculate wages and salaries from the following data: GDPmp = 4200 Depreciation = 150 NIT = - 40 Rent royalty interest = 1650 Profits = 300 Employers contribution to social security scheme = 50 Employees contribution to social security scheme = 250 Dearness allowance = 140 Mixed income = 2000