After the last day of school, everyone was looking forward to spending more time at the beach and in the pool. People were willing to pay a dollar more for each bathing suit than
they had been willing to pay in March.
What probably happened to the quantity of bathing suits supplied?

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)