\f3) Find y' of the following: a) y = 4x5 - 6x + 10 bly = Vx -! 4) A garment factory produces T-shirts, the cost of which can be worked out by the formula C(x) = x3 - 20x2 + 800. The income from the export of the T-shirts is given by: S(x) = 400 - 2x2 a) How many T-shirts need to be produced to maximize profit. b) Determine the maximum profit attainable. 5) The daily cost C, in dollars, of producing microwave ovens is C(x) =1000+ 72x -0.06.x2 where x represents the number of microwave ovens produced. a) Find the daily cost of producing 50 microwave ovens. b) Find the marginal cost function. c) Find C'(50) and interpret its meaning. d) Use the marginal cost to estimate the cost of producing 51 microwave ovens. e) Find actual cost of producing 51 microwave ovens