It is almost the end of the grading period. i have 730 out of 880 points so far in my math class which means i currently have a b (83%).there are 90 points remaining before grades come out. my teacher rounds each student's score to the nearest percent. what is the fewest number of points i need to get and end up with a grade of c (at least 70%) b (at least 80%) a ( at least 90%)

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)