A cart with mass 380 g moving on a frictionless linear air track at an initial speed of 1.3 m/s undergoes an elastic collision with an initially stationary cart of unknown mass. After the collision, the first cart continues in its original direction at 0.93m/s. (a) what is the mass (in g) of the second cart? (b) What is the speed of the two-cart enters of mass? (c) What is its speed after impact?