- 5 represents 5 minutes before a concert starts. 5 represents 5 minutes after the concert starts.
What does zero represent in this situation?
A. The number of people who are sitting after the concert starts
B. The time when the concert starts
C. The number of people who are sitting before the concert starts
D. The length of the concert from beginning to end

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)