Suspension is when particle size of solute in a solvent is more than that 100 nm
Particle size from 1nm-200nm is known as colloid
Particle size below 1nm is known as true solution
So in the given examples if we dissolve salt in water (upto its solubility) the solution obtained is known as true solution. It will not be a suspension.
In case of suspension the solute particle can be separated from solvent by simple filtration or by decanting.
When a salt like Nacl is dissolved in water we cannot separated it by simple filtration or decanting hence it is not a suspension.
