A slingshot that launches a stone horizontally consists of two light, identical springs (with spring constants of 41.3 N/m) and a light cup that holds a 1.47-kg stone. Each spring has an equilibrium length of 50.0 cm. When the springs are in equilibrium, they line up vertically. Suppose that the cup containing the mass is pulled to x= 0.700 m to the left of the vertical and then released. (a) Determine the system's total mechanical energy. J (b) Determine the speed of the stone at x=0. m/s