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In one hour, the distance, $d(s)$, in kilometers that a ferry can travel up and down a river flowing with a constant speed, $s$, in meters per second is:$\newline$$$d(s)=10.7-1.2 s^{2}$$$\newline$where $s$ and $d(s)$ are positive. Which of the following equivalent expressions for $d(s)$ contains the speed of the river in meters per second, as a constant or coefficient, for which the ferry can travel a distance of $8$ kilometers in one hour?$\newline$Choose $1$ answer:$\newline$(A) $8-1.2(s-1.5)(s+1.5$$\newline$(B) $8+1.2\left(2.25-s^{2}\right)$$\newline$(C) $8\left(1-0.15 s^{2}\right)+2.7$$\newline$(D) $11.9-1.2(s-1)^{2}-2.4$