15.) A particle moves along the x-axis such that its position 3' is x(t) = 0.2514 - 2.91613 +12.2512 -22t +21.6 for Ists 4. 2 v(t) A graph of its velocity is shown to the right. At what time does the particle reach its leftmost position? Where is the particle when it reaches its leftmost position? 5 6 -2 - 3