156. A car is moving along a straight road at a speed of $108\,\dfrac{\text{km}}{\text{h}}$. The driver sees an obstacle and applies the brakes. At a distance of $165\,\text{m}$, with a constant deceleration of $3\,\dfrac{\text{m}}{\text{s}^2}$, the car stops and remains stationary. If $t_1$ is the reaction time of the driver and $t_2$ is the time during which the car is moving after braking, which of the following is $\dfrac{t_2}{t_1}$? (1) $5$ (2) $10$ (3) $15$ (4) $20$
\textbf{156.} A car is moving along a straight road at a speed of $108\,\dfrac{\text{km}}{\text{h}}$. The driver sees an obstacle and applies the brakes. At a distance of $165\,\text{m}$, with a constant deceleration of $3\,\dfrac{\text{m}}{\text{s}^2}$, the car stops and remains stationary. If $t_1$ is the reaction time of the driver and $t_2$ is the time during which the car is moving after braking, which of the following is $\dfrac{t_2}{t_1}$?
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(1) $5$ \hfill (2) $10$ \hfill (3) $15$ \hfill (4) $20$
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