ACT Science Question of the Day

A company developed new prototype car and wanted to test the new car. The car's acceleration time from 0mph to 60mph and stopping time from 60mph to 0mph were measured. An obstacle course involving a lot of turns was also constructed to determine how well the car can handle turning. The main concern of the company is the safety of the car and therefore all of the tests were performed on dry concrete, concrete after simulated rain, concrete that was covered with snow and in sand.

In order for the car to be safe on the roads, it is necessary for the car to have a stopping time of 4.5 seconds. What surfaces would the car not be safe on?