Q3) [12+ 4 = 16 Marks] A rocket approaching Earth at velocity v has a headlight which is seen by an observer on Earth to have wavelength A. After the rocket passes the Earth it recedes with the same velocity and the rocket's taillight (which is physically identical to the headlight) is observed on Earth to have a wavelength . a) If 2=2A, then what is 2 b) If 450nm, then what is the wavelength as measured by an observer onboard the rocket?