Explanation: Oxygen cycle is the process by which oxygen is released into the atmosphere by photosynthesis and is used by aerobic organisms while the carbon dioxide is released as a by product of respiration. This carbon dioxide is used in photosynthesis for production of glucose.
Hence, for oxygen to remain in the atmosphere, it has to circulate through various forms of nature and this circulation of oxygen is called as oxygen cycle.
Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy. (I believe this is it)