Answer:A star with a planet will move in its own small orbit in response to the planet's gravity. This leads to variations in the speed with which the star moves toward or away from Earth, i.e. the variations are in the radial velocity of the star with respect to Earth. The radial velocity can be deduced from the displacement in the parent star's spectral lines due to the Doppler effect
Cancer is an irregularity that occurs when cells mutate in a harmful way. This causes abnormal cell growth that is uncontrollable. These cell growths become tumors that, based on the type, may or may not spread to other parts of the body.
