The average value of sqrt 3x on the closed interval [0,9] is?

Tiffany drives 285,120 feet before lunch and 628,320 feet after lunch. about how many kilometers does she drive all together

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)

Math question.. plz me .. best answer all