Light is gathered from a distant galaxy and one of the spect

Light is gathered from a distant galaxy and one of the spectral lines is observed at 540 nm when it should be 400 nm. The velocity of this galaxy is ______km/s. (Do not include units. If your answer is negative, include minus sign.)

velocity = (540-400)c/400 = 140* 299792.458/400 = 104927.360