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12) Minimum he location of the indicated absolute extremum for the function The A) x -0 Solve the problem. Bj x =-3 C) x = -4 D) x = 2 13) If the price charged for a bolt is p cents, then x thousand bolts will be sold in a certain hardware store, where p = 71 - How many bolts must be sold to maximize revenue? 131 A) 1207 thousand bolts C) 2414 bolts B) 2414 thousand bolts D) 1207 bolts 14) Suppose c(x) =x3 - 18x2 + 20,000x is the cost of manufacturing x items, Find a production level that 14) will minimize the average cost of making x items. A) 8 items B) 9 items C) 11 items D) 10 items 15) An engine cylinder 16.1 c deep is being bored such that the radius increases by 0.14 mum/min. 15) How fast is the volume V of the cylinder changing when the diameter is 7.6 am? A) 384 cm3/min B) 5.4 cm-/min C) 54 cm3/min D) 10.2 cur / mun Find the points of inflection. 16) 16) y= -x4-x3+15 A) (0, 0) B) (0, 0) and (2, -4) C) (0, 0) and (2, 11) D) (0, 15) and (2, 11) The function f changes value when x changes from a to a + dx. Find the true change Af = fla +dx) - fla) and estimated hange df = f(a) dx. 17) 17) f(x) = 3x + 2, a=5, dx =4 B) 16; 12 C) 16; 16 D) 14; 12 A) 12; 12 A-3