Yo free brainliest and 100 points

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)

Will give brainliestbased on the topographic map of mt. st. helens, what is the contour interval if the volcano height is 2,950 m?

Darragh has a golden eagle coin in his collection with a mass of 13.551\,\text{g}13.551g. an uncirculated golden eagle coin has a mass of 13.714\,\text{g}13.714g.