2. (a) Sketch the first four standing waves (n = 1, 2, 3, 4) on a string of length L that is fixed at both ends. Mark the positions of the nodes (N) and antinodes (A). (b) Consider a wave with a wavelength of 1.5L. Could this wave produce a standing wave on the string? Use a sketch of what this "standing wave" would look like to explain your