Akhira started her own landscaping business. She charges $6 an hour for mowing lawns and $11 for pulling weeds. In September she mowed lawns for 63 hours and pulled
weeds for 9 hours. How much money did she earn in September?

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)