Tell me the answer and explain it to me i really need it

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 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)

Which fraction is equal to 1hole and 2/5? a.3/5 b.75 c.57 d.73

Common binomial factor of 6x(3x+7)+5(3x+7)