How would your energy graphs look DIFFERENTLY if the mass was 1 kg instead of 0.5kg?
The energy graphs would look different by having higher peaks on the upside down parabola. The spring would have need to exert more energy. which in this case would cause a change in the graph. The numbers on the graphs was for how much energy was need for the 0.5kg mass. The numbers would change because there was more energy needed to move the 1kg mass in the harmonic motion presented in the first graphs.