As seen in the lab frame a rocket A is moving to the right

Question

with speed c  and rocket B is moving to the left with speed
c  . The pilot of rocket B fires a laser beam. In the B-frame,
the laser beam points in the x-y plane and makes and angle
=53.13˚ with the x-axis. (It has a positive x- component of
velocity and a positive y- component of velocity).
a) Find the x and y components of velocity of the laser beam
in the B-frame.
b) Show that the speed of the rocket B as seen by the observer in the A-frame is  u Kc where
2
2
1




K .
c) Find the x and y components of velocity of the laser beam as seen by the observer in the A-frame in terms of K.
d) Find the angle between the laser beam and the x-axis as measured by the observer in the A-frame in terms of K.
e) For what value of  does A see the laser pointing
along the y-direction?