a) (3 marks) The mass distribution by particle size for the feed is given by the following table. Determine the F80. Sketch the graph and indicate how do you get your answers from the graph to the nearest microns. (You may use excel to help you with the sketch) b) If the product screen size (S) is 190m,G1.54g/rev and P80200m. i) (1 mark] Calculate the Band work Index (Wi) in kWh/t, using the formula below w1=s0.23G0.82(P0010F1010)49.04 ii) (1 mark) Calculate the current energy required (W) for ultra-fine grinding Fas1000m to a final Pk0150m, using the formula below W=wi(P8010F8010) iii) (3 marks) The company required the ore to be further fine-grind to increase liberation of the mineral. However, the process is constraint by the cost of energy. If the maximum energy cost could only be doubled the current energy use, what is the minimum grind size we can achieve? Explain using Energy - P8o Plot