2. A particle moves along a straight line starting at t = 0. Its position is given by the equation \( x(t) = 75t - 1.0t^3 \), where t is in seconds. When it stops (v=0), its acceleration is:
(A)0
(B)-73 m/s²
(C)-30 m/s²
(D)-9.8 m/s²

(E)49 m/s²

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