A car travels at 18 m/s. Its stopping distance is 45 m and its braking distance is 31.5 m. What is the reaction time of the driver?
1.33 s1.33\ \mathrm{s}1.33 s
1.75 s1.75\ \mathrm{s}1.75 s
2.50 s2.50\ \mathrm{s}2.50 s
0.75 s0.75\ \mathrm{s}0.75 s