"has eaten" is this singular or plural

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)

Explain how you divide powers with like bases.discuss why the bases have to be the same.how are these rules similar to the rules for multiplying powers with like bases.

Ataxi company charges $3 for pick-up plus $0.65 for each mile. select the expressions that represent the cost in dollars for a taxi pick-up and m miles. mark all that apply.