If you know this multiple choice I think I know the answer but making sure

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)

There are 45 questions on your math exam. you answered 810 of them correctly. how many questions did you answer correctly?

Harry the hook has 7 1/3 pounds of cookie dough.she uses 3/5 of it to bake cookie. how much cookie dough does she use to make cookie?