Please solve with steps

Consider a simple wave-like pattern. When measured in the north-south (i.e., y) direction the peak-to-peak distance is 489 m. When measured in the east-west (i.e, x) direction, the peak-to-peak distance is 281 m. a) Find k and determine in which direction it points (i.e., angle with respect to north). b) Sketch a contour map of the pattern assuming the amplitude varies between +1