Answer
(a) The speed of the laser beam relative to Sam is $c$.
(b) The speed of the laser beam relative to Tom is $c$.
Work Step by Step
(a) One of Einstein's postulates in special relativity is that the speed of light is $c$ in all frames of reference. Therefore, the speed of the laser beam relative to Sam is $c$.
(b) One of Einstein's postulates in special relativity is that the speed of light is $c$ in all frames of reference. Therefore, the speed of the laser beam relative to Tom is $c$.