What is the measurement of how fast an object moves relative to a reference point?

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.

Explain what will happen if decomposers were apsent from a forest ecoysystem.

How much work would it take to move a coulomb charge across a 4 volt potential difference?