Arranged in an orderly pattern. We know that there are three states of matter, land, water, and gas and all have different arrangement of particles. It is the solid that has an orderly arrangement while gas has the most spread apart arrangement.
I would think energy has been transferred <span />
<span>Sample #2 and sample #3 must have the equal volume as sample #1 ,if the masses of the both samples are equal to mass of sample #1.
Otherwise, the volume would vary if the masses are not equal.</span>