A production process has joint costs of $12,000 for the input of 1,000 kgs of material. Two products are produces from this: Product A: 600 kgs. Selling price = $25/unit. Separate costs = $4,000 Product B: 400 kgs. Selling price = $40/unit. Separate costs = $7,000 Calculate the inventory value of the production using (a) Weigh to apportion the joint costs (b) Net realisable value to apportion the joint costs