What is the ruling on selling live chickens by weight,
and on selling vinegar that contains 6% alcohol?
it is permissible to buy chickens by weight. This is the basic principle and we do not know of any evidence to the contrary.
it was authentically reported from the Prophet (peace be upon him) that he said:
"Whatever intoxicates in large quantities, a small amount of it is Haram (prohibited).
If the vinegar would cause intoxication in large amounts, then a little of it is Haram, (Part No. 13; Page No. 53) and it comes under the same ruling as wine. If a large amount of it does not cause intoxication, then there is no reason not to sell, buy, or drink it.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.