Question $14(3\mathrm{.}5$ points$)$

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Three boxes are lined up so that they are touching each other on a nearly frictionless plane. Box A has a mass of $m_A=22\mathrm{.}0kg,$ box B has a mass of $m_B=30\mathrm{.}5kg,$ and box C has a mass of $m_C=53\mathrm{.}0kg.$ An external force vec$(F)$ pushes on box A toward the right, and the force that box $B$ exerts on box $C$ has a magnitude of $199$ N Ignore friction. What is the magnitude of the acceleration $a$ of the boxes?

$3\mathrm{.}75\frac{m}{s^2}$

$3\mathrm{.}50\frac{m}{s^2}$

$4\mathrm{.}25\frac{m}{s^2}$

$3\mathrm{.}25\frac{m}{s^2}$