If a wave has a period of 0.5 s, what is its frequency

The dot diagram represents the motion of the motorcycle as it moves from left to right

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?

This is the number of complete movements of a wave per second.