3. The figure depicts a triangular pulse propagating along a string that lies along the v-axis, on its way to the end of the string at the vertical blue line located at the x-position a distance of 10 cm from the origin (each gridline is 1 cm square). The wave is traveling at a speed of 'l cmfs. The end of the string at the blue line is free to move vertically. f3. a. Find the velocity (speed and direction) of the particle of string located at the center of the leading segment of the wave at the moment depicted in the figure. b. As accurately as possible, sketch the wave 4 seconds after the moment captured in the gure