\textbf{117.} Find the value of $\displaystyle\lim_{x \to -\frac{1}{2}^-} \dfrac{10x - 5 + \left[\dfrac{3}{x^2}\right]}{16x - \left[-\dfrac{7}{x^2}\right]}$. (Here $[\,]$ denotes the floor function.)
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(1) $-\infty$ \hfill (2) zero \hfill (3) $\dfrac{5}{8}$ \hfill (4) $+\infty$
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