Explanation:
Below is an attachment containing the solution.
Mass number<span> is the </span>number<span> of protons </span>and<span> neutrons in an atom.
</span>Atomic mass<span> is the average </span>mass<span> of all the isotopes of a certain type.</span>
The battery gives energy to the connected light and switch, and the switch controls the light.
Answer is: the nature of the initial nickel sulfide mixture is a suspension.
Suspension<span> is a </span>heterogeneous mixture (solute<span> particles do not </span>dissolve), <span>that contains </span>solid<span> particles (in this example nickel sulfide or NiS) sufficiently large for </span>sedimentation. <span> The internal phase (solid nickel sulfide) is dispersed throughout the external phase (water).</span>
