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24. The demand for grass seed (in thousands of pounds) at price p dollars is given by the following function. D(p) = -3p3 -2p2+ 1469 Use the differential to approximate the changes in demand for the following changes in p. a. $3 to $3.15 b. $6 to $6.12 a. The change in demand based on a change in p from $3 to $3.15 is about thousand pounds. (Type an integer or a decimal.) b. The change in demand based on a change in p from $6 to $6.12 is about thousand pounds. (Type an integer or a decimal.) ID: Bus Econ 6.6.17 25. Evaluate. 1 (9X516-12x1/5) dx S (9X5/6 -12x 1/5) dx = ID: 7.1.19 26. Find the cost function for the marginal cost function. C'(x) = 0.06 e 0.02%; fixed cost is $5 C(x) = ID: Bus Econ 7.1.47 27. Use substitution to find the indefinite integral 25 (5x + 8)6 Ox. 25 (5x + 8)6 Ox = ID: 7.2.5 28. Use substitution to find the indefinite integral. 5 x 4 @ 8x5 dx 5x4 @ 8x5 dx =