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The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

The cost of turkey is directly proportional to its weight. if a 12-pount turkey costs $27, how much does a 16-pound turkey cost? a. $33.75 b. $36.00 c. $31.00 d. $32.50

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length