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The movement of an object is described by the position function:

$${\bf r}(t)=t{\bf i}+t^3 {\bf j}+ (2t-1){\bf k}$$

What is the acceleration of the object when it is at the point $Q=(3,27,5)$?

$3{\bf i}+18{\bf j}$

$3{\bf i}$

${\bf i}+27{\bf j}+2{\bf k}$

$18{\bf j}$

$3{\bf i}+18{\bf j}+5{\bf k}$