Two objects start combined together . Object one has a mass of 10.0 kg and object two has a mass of 5.0 kg . Combined they are at rest, however they interact and object one pushes away at 4.0 m/s to the right . What will object two's velocity be at this point ?

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?