I'm not sure if this is your question but with NaCl (salt) and water it is homogeneous because when mixed, all the salt particles are even throughout and diffuse throughout the water.
The answer is - D. are constantly in motion
These plates move back and forth and sometimes even end up going one above other
The answer is 0.492 because there are 100 meters in a hectometer, and 49.2/100 is 0.492
If the force is applied to lift the box, then there is no work done as the displacement of the box is not in the same direction of the box.
However, if the force is being applied to move the box in the direction of the force, then the work done is:
Work = force x distance
Work = 1500 x 3
Work = 4,500 Joules