C(x)=0 0122 -0.3x2 + 8x gives the cost, in thousands of dollars, to produce x thousand items (a) Find a formula for the marginal cost. (b) Find C'(o). Give units (c) Graph the marginal cost function. Use your graph to find the minimum marginal cost, the production level for which the marginal cost is the smallest (d) For what value of x does the marginal cost return to C'(0)? (a) Find a formula for the marginal cost C