On the track team, 3/5 of the members are boys. of these boys, 4/7 are sixth graders. of the sixth-grade boys on the team, 1/3 are runners. what fraction of the track team are sixth-grade boy runners?

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)