MASS OF THE STAR IS 10 TIMES OF THE SUN. M = 10Msun HERE, Msun IS THE MASS OF THE SUN. THE RELATION BETWEEN THE LUMINOSITY AND THE MASS OF THE STAR IS L = M3.5 HERE, M IS THE MASS OF THE STAR, SUBSTITUTE 10Msun for M L = (10Msun)3.5 => (10 3.5)Msun3.5 from the above result, it is clear that the luminosity of the star is approximately 10 times that of the sn. Therefore the luminosity of the star is 10 solar units.