To pour the concrete sidewalk shown in the figure, approximately how many cubic feet of topsoil will you need to remove for the 4"-thick sidewalk if the owner wants the finish surface of the sidewalk to be level with the adjacent topsoil? ROUND YOUR ANSWER TO THE NEAREST CUBIC FOOT. _ cu ft

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 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)