Simplify the following expression

Scale factor of 2 is used to enlarge a figure as shown below the area of is 18 in.²

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 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)

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.