3. Given a Cobb-Douglas production function of Q = 100K .4[-5: a) Determine and interpret the returns to scale. determine the b) If the cost of capital (C) is $80 per and the cost of labour (W) is $50 per unit, optimal capital - labour ratio. employed and c) If the profit-maximizing output is 3,200, how much capital and labour would be what would be the total cost? d) Now suppose that the price of capital decreases to $60 per unit: i) Determine the optimal capital-labour ratio. What is the ii) How much labour and capital would be employed to produce an output of 3,200? substitution effect for labour