What is a explanation of physical weathering

Apiano tuner uses a tuner to create a tone of 5.00 x 10² hz. when a key on the piano is struck he hears 5 beats per second. what is a possible frequency of vibration for the piano string? 2500 hz 1300 hz 605 hz 495 hz

Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

How do you tell if someone actually cares about you? and just say they do?