A minibus is driven on a dry test track at two different speeds. On each run, the driver's reaction time and the total stopping distance are measured.
| Speed in km/h\mathrm{km/h}km/h | Reaction time in s\mathrm{s}s | Stopping distance in m\mathrm{m}m |
|---|---|---|
| 45 | 0.64 | 18 |
| 90 | 0.80 | 60 |
1 m/s=3.6 km/h1\ \mathrm{m/s}=3.6\ \mathrm{km/h}1 m/s=3.6 km/h
Calculate the ratio of the braking distance at 90 km/h to the braking distance at 45 km/h.
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