Question Income
Part-time job: $700 /month
College fund from grandparents: $350/month
Scholarship: $4800 / year
Expenses
Rent: $550/month
Groceries: $70/week
Tuition and fees: $2400 twice a year
Incidentals: $140/week

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)