Experiments show that if the chemical reaction N2O5→2NO2+1/2O2, takes place at 45°C, the rate of reaction of dinitrogen pentoxide is proportional to its concentration as follows: -d[N2O5]/dt = 0.0005[N2O5] How long will the reaction take to reduce the concentration of N2O5 to 90% of its original value?

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)