When is the plural used in English numerical units There are all kinds of opinions on the Internet. I want a clear and authoritative answer

When is the plural used in English numerical units There are all kinds of opinions on the Internet. I want a clear and authoritative answer

1. 0.5 ℃ 2, 0.5 m3, 0.5 s 4, 0 s 5, 0 ℃ 6, negative 5 ℃ 7, 0 m
1, 0.5 degrees 2, 0.5 meters 3, 0.5 seconds 4, 0 seconds 5, 0 degrees 6, negative 5 degrees 7, 0 meters