Answer both parts please

On a highly polished. essentially frictionless lunch counter. a 0.540 kg submarine sandwich moving 3.50 m/s to the left collides with a 0.250 kg grilled cheese sandwich moving 1.25 m/s to the right. For related probiem~solving tips and strategies, you may want to view a Video Tutor Solution of Inelastic collision on an air track. V PartA v It the two sandwiches stick together, what is their final velocity? Express your answer with the appropriate units. Enter positive value it the direction of the velocity Is to the right and negative value if the direction of the velocity is to the left. BANG)? v= Value Units m MuestAnswer Part B How much mechanical energy dissipates in the collision? Express your answer with the appropriate units. l EuAMC)