The chamber is now filled with a gas that has an unknown speed of sound. The students find that the lowest frequency at which they can hear a maximum in the sound level is 200 Hz. If the students slowly increase the frequency, what is the next frequency at which the sensor would measure a maximum in the sound level

You are driving to the grocery store at 20 m/s. you are 110m from an intersection when the traffic light turns red. assume that your reaction time is 0.50s and that your car brakes with constant acceleration. how far are you from the intersection when you begin to apply the brakes? what acceleration will bring you to rest right at the intersection? how long does it take you to stop after the light changes? the known values: vi=20m/s xi=110m t=.50s vf=0m/s xf=0m a=?