You are a driver responding to the traffic light in the previous exercise. If it was correctly designed according to that problem, at what distance from the light should you be prepared to make your “to stop or not to stop” decision? Assume you are a safe driver who neither speeds up to get through the yellow light nor stops more suddenly than the deceleration rate of -5.0 m/s².

Previous exercise. 

You are an engineer designing a traffic light. Assume a person can see a traffic light change color from red to yellow, and it takes one second to respond to a change in color. Suppose the speed limit is 15. m/s. Your goal is to enable drivers always to stop after seeing and responding to the yellow light with a maximum deceleration of -5.0 m/s². How long should the yellow light last?