Waves are ?
that can travel through matter.

A wave can be thought of as a disturbance or oscillation that travels through space-time, accompanied by a transfer of energy. The direction a wave propagates is perpendicular to the direction it oscillates for transverse waves. A wave does not move mass in the direction of propagation; it transfers energy.

oscillating motion

Explanation:

you go to your settings preference and in the end youll see sth that says "i want to delete my acc" click on it and u'll acc will be deleted but u have to wait.

because growing process had stoped after 4-5 year