How can poor posture result in back pain?

Ahanging spring stretches by 35.0 cm when an object of mass 450 g is hung on it at rest. in this situation, we define its position as x = 0. the object is pulled down an additional 18.0 cm and released from rest to oscillate without friction. what is its position x at a moment 84.4 s later? express your answer in cm.

What is the increase in density of a medium due to wave travel?

The solid that is formed and usually sinks to the bottom of a solution is the