Hint 8-63

The technique is to draw down the molecule, substitute one of the Hs which you are examining for equivalence
with a test atom (eg. chlorine) and then name the molecule.
You then redraw the molecule with the other H which you are checking for equivalence substituted by your test atom
and name this second case.
If the names for both cases are the same then the Hs are equivalent,
if the names are different then the Hs are not equivalent.