10.15. Consider a medium PRF radar on board an aircraft moving at a speed of 350 m/s with PRFs f,1 = 10KHz, fr2 = 15KHz, and fr3 = 20KHz; the radar operating frequency is 9.5GHz. Calculate the frequency position of a nose-on target with a speed of 300 m/s. Also calculate the closing rate of a target appearing at 6, 5, and 18KHz away from the center line of PRF 10, 15, and 20KHz, respectively.