PLEASE HELP ASAP A particle moves along a straight line. For 0 ≤ t ≤ 5, the position of the particle is given by s(t)= 3t+ 4t^2 - t^3

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a) What is the average velocity of the particle over the interval 0 ≤ t ≤ ?
b) Find a general expression for the velocity of the particle as a function of time, v(t), and determine
the value of v at t = 2. Is the particle traveling to the left or the right at this point? Justify your
answer.
c) Find all times t during the interval 0 ≤ t ≤ 5 that the particle changes direction. Justify your
answer.
d) At t = 4, is the speed of the particle increasing or decreasing? Justify your answer.