Guess what, Canada sets the freezer at -15 Celsius. The USDA just chose 0F because it’s good enough and a nice easy to remember number, there is nothing special about it.
Same with all your other numbers, your just using whatever the closest even F value is that’s easy to remember there’s nothing special about any of them and we have equivalents in Celsius
Not sure where you got -4F from.
USDA, United States Department of Agriculture, recommends 0°F or -17.8°C
100°F in the shade isn’t extreme, and you’d be able to survive normally (With more water, everyone can use more water)
100°F is hot tub water
120°F is recommended hot tap water
140°F water will pretty much burn you instantly
Guess what, Canada sets the freezer at -15 Celsius. The USDA just chose 0F because it’s good enough and a nice easy to remember number, there is nothing special about it.
Same with all your other numbers, your just using whatever the closest even F value is that’s easy to remember there’s nothing special about any of them and we have equivalents in Celsius