I went to eat and my class ended help plzz (Pattern must be Claim, evidence, reasoning)

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)

What is always true when two whole numbers are subtracted?

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c