A test of a driver's perception/reaction time is being conducted on a special testing track with wet pavement and a driving speed of 50 mi/h.
When the driver is sober, a stop can be made just in time to avoid hitting an object that is first visible 385 ft ahead.
After a few drinks under exactly the same conditions, the driver fails to stop in time and strikes the object at a speed of 30 mi/h.
Determine the driver's perception/reaction time before and after drinking. (Assume practical stopping distance.)