What is 2/3x + 1/6 = 4/3x

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)

This is about circle theorems. someone asap : (

Question 4 of 10 2 points what is the second part of the process of investigating a question using data? a. rephrasing the question o b. describing the data c. collecting the data o d. making an inference submit