Section Area (m2) Zn Grade (%) Pb Grade (%) A1 1,800 5.10 6.75 A2 1,400 4.80 8.20 A3 1,740 4.90 7.30 A4 1,380 3.80 6.20 A5 1,800 5.20 9.10 Required: (11) (iii) Calculate by using the weighted methods the average grades for Zn and Pb Estimate the total tonnage for the polymetallic reserve base If the project's extraction period to completion is 3 years, calculate the annual profits for the project given the following information: Price for Zn is $1.5/kg and $1.85/kg for Pb Mining and processing cost is $150/tonne Metallurgical recovery is 90% for Zn and 85% for Pb Attach a fair monetary price to the project at 5% discount rate . (iv) Section Area (m2) Zn Grade (%) Pb Grade (%) A1 1,800 5.10 6.75 A2 1,400 4.80 8.20 A3 1,740 4.90 7.30 A4 1,380 3.80 6.20 A5 1,800 5.20 9.10 Required: (11) (iii) Calculate by using the weighted methods the average grades for Zn and Pb Estimate the total tonnage for the polymetallic reserve base If the project's extraction period to completion is 3 years, calculate the annual profits for the project given the following information: Price for Zn is $1.5/kg and $1.85/kg for Pb Mining and processing cost is $150/tonne Metallurgical recovery is 90% for Zn and 85% for Pb Attach a fair monetary price to the project at 5% discount rate . (iv)