Ahighway patrol officer uses a device that measures the speed of vehicles by bouncing radar waves off them and measuring the doppler shift. in one such instance, the outgoing waves had a frequency of 100 ghz and the returning echo had a frequency 15 khz higher. assume the officer is facing in the positive direction. what is the velocity of the vehicle? note that there are two doppler shifts in echoes. be certain not to round off until the end of the problem, because the effect is small.