please answer it in detail

2. You have just been pulled over for running a red traffic light, and the police officer has informed you that the fine will be $250. In desperation, you recall the doppler shift from your physics class. You tell the officer that the light appeared green to you because of the doppler shift. You explain that the frequency of light shifts if an observer if moving toward or away from a source. Unfortunately, the police officer did very well in her physics course. She says "OK, then I'll ticket you for speeding. The fine will be $1 for every km/hr over the posted speed of 50 km/hr." How big is your fine? Use 650 nm for the wavelength of red light and 540 nm for the wavelength of green light