Two waves are traveling simultaneously down a long Slinky. They can be represented by the following equations. Y, (x, t) = 0.00420 sin(6.00x - 354t) I2(x, t) = 0.00420 sin(6.80x - 250t) Distances are measured in meters and time in seconds. (a) Write the expression for the resulting wave. (Use the following as necessary: x and t. Do not include units in your answer.) Y = X (b) What are the phase and group velocities (in m/s)? (Enter the magnitudes.) phase velocity * m/s group velocity m/s (c) What is Ax (in m) between two adjacent zeros of '? (Enter the magnitude.) m (d) What is AkAx (in rad)? rad