Can anyone please help me with this?

Law of Sines

sin (pi/6) / (3x)  = sin B / ( x )             simplify

(1/2) / 3  = sin B

sin B  = 1/6

12 sin (B )  = 2

Since  sin B  = 1/6         then the altitude must be  1   and  x  must be 2   

Using the Law of Sines again

sin (pi /6) / (3x) =  sin (C) /AB

(1/2) /  6  =  sin (C) / AB

(1/12) = sin (C) / AB

sin C  =  AB / 12

So

12 sin C   =  AB