Solve this equation by using the look inside method to rewrite the problem

-81 = 3(5 - 4r)

Can someone me with this problem i don't understand i need

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)

Whats the theoretical probability of popping a polka dot balloon? express your answer as a fraction, decimal and percent solid 15 polka dot 5 striped 17 plzz me due tomorrow