Big ideas integrated 1 chapter 8 test? anyone ?

Acircle has a circumference of 28.36 units what is the diameter of the circle

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)

The acceleration of an object due to gravity is 32 feet per second squared.what is acceleration due to gravity in inches per second squared?