Smith Limited makes a single product, the unit cost of which is budgeted as follows: Rs Direct materials 200 Direct labour 800 Variable production overhead 400 1,400 Additional information: (i) Sales in units for 2019 are expected to be as follows: January 6,000 February 6,600 March 7,200 April 7,400 May 7,000 The selling price is Rs2,000 per unit and is not expected to change in 2019. (ii) 70% of each month invoiced sales are produced in the previous month with the remainder being produced in the month of sale.