The law of conservation of matter tells us that the total number of atoms does not change in a chemical reaction and thus mass is conserved. Select all of the reactions that obey the law of conservation of matter

A10 kg box initially at rest is pulled 18 meters across a horizontal, frictionless surface by a 40 n force. what is the block’s final velocity over the 18 meters?

What quantity do units represent in value

Would it be correct to say the doppler effect is the apparent change in the speed of a wave due to the motion of the source? be sure to fully explain your position using at least 3 complete content related sentences.