A physics teacher is demonstrating a spring in her lab to her students. The spring, having a spring constant of 40 N/m, is in a horizontal orientation, and one of its ends is fixed. A small metal ball of mass 90 g is attached to its free end. The teacher makes the metal ball oscillate by compressing the spring by 3.0 cm first and then letting go. The spring, as a result, oscillates back and forth with the same amplitude. Afterward, the teacher draws a graph on her board corresponding to the motion of the spring. If she assumes that friction and the mass of the spring are negligible, determine the speed of the ball at the distance from the equilibrium x = 2.5 cm, from her graph given below.