12. Which of the following will always be true of a graph that is non-proportional?
A. The graph will have a negative slope.
B. The graph will have a positive slope.
C. The graph will pass through the origin.
D. The graph will not pass through (0, ).

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)