A 6 m thick coal seam in Queensland sub-crops 45 m below the natural surface. The overburden consists of sandstone, siltstone and some mudstone. However, the upper 10 m overburden is well-weathered clayey material, and it may be stripped without blasting. The quality of the resource indicates that it should produce medium-hard coking coal with an overall expected yield or coking coal recovery at 70%. Currently, a market for 2.3 million tonnes per year of coking coal exists. The company is evaluating the prospective acquisition of one of the following two draglines: Dragline A: Bucket capacity = 45 m3 Cycle time = 60 seconds Availability = 92% Utilization = 90% Dragline B: Bucket capacity = 60 m3 Cycle time = 63 seconds Availability = 91% Utilization = 90% In-situ (bank) rock density = 2.3 tonne per m3 In-situ (bank) coal density = 1.35 tonne per m3 Dragline rehandle = 40% Overburden average percent swell = 20% Bucket fill factor = 95% Dragline deadhead (movement) between pits = 3 days per year Allowance for wet weather interference = 2 days per year Major rebuilds (maintenance) time = 6 weeks every 4 years (a) Given the information above, Determine both draglines annual capacities (production) in bank-m3 per year, and draglines prime rates in bank-m3 per year. (b) Also, given the coking coal demand, determine run-of-mine (ROM) coal requirement in tonnes per year, ROM coal requirement in bank-m3 , stripping ratio in bank-m3 per tonne of coal, waste removal requirement in bank-m3 per year. (c) Identify, which dragline would be more suitable for this operation. (d) Or would you suggest another dragline for purchasing that will meet the stripping requirement per year. If so, please investigate for a new model.