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Central Africa Mining Corporation (CAMC) is considering reopening a coppermine in northern Zambia. The following data was obtained for the two options that CAMG can employ to extract the copper: Cash Flow E Millions EMons 120 -60 +20 +40 -E50 +30 Both options have substantial cash flows at the end of year S. since machinery has to be decommissioned and land must be returned to green field' status. The company's cost of capital is 10%. The newly appointed financial director of CAMC has decided to replace IRR with MIRR for investment appraisals within CAMC Caleulate modified internal rate of return for open cast and deep mine methods