a. Construct an explanation for why three H's attached to the same carbon (a methyl...

a. Construct an explanation for why three H's attached to the same carbon (a methyl group) are equivalent (for example, see the structures above and below).

b. Construct an explanation for why the two CH₃ groups on the structure above are equivalent (making all 6 H’s labeled “b” equivalent), but the two CH₃ groups on the structure at right are NOT equivalent