distilled water,0.9M NaCl solution & 20% NaCl solution, which solution is isotonic, hypertonic and hypotonic?

Answer 1

As Chemistry points out, it depends on what the
solution is being compared with. In comparing A
with B, A is isotonic to B if it contains the same
solute concentration as B, hypotonic if it contains
a lower concentration and hypertonic if it has a
higher concentration. Since different organisms
have different solute concentrations in their body
fluids the tonicity of a solution will be different
for different organisms being compared.

Answer 2

Distilled water is hypotonic
0.9M NaCl solution is isotonic
20% NaCl solution is hypertonic

Answer 3

With regards to what?

(You've gotta compare them against something if you want to make a statement about whether they're isotonic/hypotonic/hypertonic.)

Answer 4

0.9M NaCl ---- isotonic
20% NaCl solution ---- hypertonic
distilled water---- hypotonic

This is with respect to the human body condition.