Two travelling sinusoidal waves are described by the wave functions
Y_{1} = 55.00 sin [π (4.00x - 1200t)]
Y_{2} =55.00 sin [π (4.00x - 1200t - 0.250)]
Where x, Y_{1}, and Y_{2} are in meters and t is in seconds.
(a) What is the amplitude of the resultant wave function Y_{1}, and Y_{2}?
(b) What is the frequency of the resultant wave function?