Beeesneees,
1.
It will be difficult to maintain a six pack.
What is the meaning of ‘six packs’?
2.
“The nurse packed gauze on/in the wound.”
Which preposition is correct for this sentence?
‘six-pack’ not ‘six-packs’ here.
You could have been independent in finding out that information:
oald8.oxfordlearnersdictionaries … y/six+pack
Definition 2.
- In my opinion, neither, as you do not pack gauze into or onto a wound.
You place it (not pack it) on a wound.
You might pack gauze around a wound (to protect it from further damage before it can be dressed properly).