Sally works 40 hours and makes $20 an hour, but her kids are in child care each day and the day care center charges her $50 per day. if you deduct her child care expenses, how many dollars per hour does she actually make? (assume sally works five days per 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)