Aspeeder is driving down the road at a constant 15 m/s, passes a police officer parked on the roadside. the officer pauses 9 seconds, then pursues the speeder, accelerating at a constant 5 m/s^2.
how much time does it take the police officer to catch the speeder?
how far did the police officer drive before the speeder was caught?

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?