Ronny, celina, jack, and michelle together placed a total of 20 brownies on a tray. ronny placed 0.15 of the brownies, celina placed 3 of the 20 brownies, jack placed 30% of the brownies, and michelle placed the remaining brownies. who placed the most brownies?
ronny
celina
jack
michelle

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)