Costs and net profit Given the following information. Left pit wall overall slope angle: 52 Underground total mining cost: $37.50 /tonne Surface mining cost: $21.25 /tonne Surface stripping cost: $3.90 /tonne of waste Density of ore: 2750 kg/m3 S.G. of waste: 1.8 Strike length of orebody: 485 m Grade of gold ore: 8.2 g/tonne Dilution: 0 % Gold bullion selling price: $1150/oz Mill recovery: 92% Milling cost: $32 /tonne Tax rate: 32% The orebody outcrops at the surface. The existing surface is flat/level When underground mining at this operation should be contemplated, calculate: The total cost of mining the ore of the open pit. The total cost of mining the waste of the open pit. The expected net profit after income taxes for the life of the pit operation