Every year, Liberty High School holds a relay race during a field day. If y represents the winning time for the relay race in seconds and x represents the number of years after 2000, then the equation y=−0.09x+12.94 can be used to model the winning times in the relay race at the Liberty High School field day after 2000. According to the linear model, what was the winning time in the relay race in seconds at the Liberty High School field day in 2007?

12.85 seconds

12.31 seconds

12.22 seconds

12.04 seconds

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)