A cyclist has a reaction time of 0.60 s. During this reaction time, the cyclist travels 4.2 m at a constant speed before starting to brake. What is the cyclist's speed?
7.0 m/s7.0\ \mathrm{m/s}7.0 m/s
3.6 m/s3.6\ \mathrm{m/s}3.6 m/s
0.14 m/s0.14\ \mathrm{m/s}0.14 m/s
2.5 m/s2.5\ \mathrm{m/s}2.5 m/s