Legionella won’t make you sick if you drink it, only if you breathe it in. It exists in clean drinkable water all over the world. It’s capable of hibernation and able to survive without nutrients for long periods. So it’s at least a potential risk any time you breathe aerosolized particles from water that is not hot enough to kill it. Any type of water heater that heats to 60 degrees Celsius will kill it.

This is a great idea if you are the only one using your shower. If you have 4 family members, each of whom likes a different shower temperature, it is less ideal. I think controls that allow separate on/off and hot/cold dimensions are best for most scenarios.

American customary units and imperial units both come from English units, so the US used various inconsistent English and other units in its early days. But the US never used “Imperial” units, which were not codified and put into effect in the British Empire until almost 50 years after the US had gained independence.

Perhaps the Giant London Flea Market will start a trend: https://www.queenelizabetholympicpark.co.uk/whats-on/giant-london-flea-market

A number of Slavic, Baltic, Norse, (and also Finnic languages like Finnish and Estonian) use some form of this word for market. It originated in Proto-slavic and passed through Old Norse into descendant languages.

https://en.m.wiktionary.org/wiki/търгъ#Old_East_Slavic

The most interesting thing is that the root appears to have borrowed into Finnish twice, once probably from Slavic (as turku) and once from Old Norse (as tori).

It’s debated. One source points to the lower end of the scale established as the freezing point of a brine made by dissolving ammonium chloride in water.