English units have some advantages.
For instance: Farenheit:
* 100 degrees was intended to be the normal internal temperature of a healthy, awake, resting human, though the scale originally set mouth temperature as 98 for a proxy. (Typical "normal" is 98.6 under the tongue, 100.6 rectal, after the scientists tweaked it to make the freezing and standard-pressure boiling points of water exactly 180 degrees apart, so they got it pretty close.) Makes understanding fever readings easy.
* zero degrees is the melting point of water in saturated (ammonium chloride) salt solution - the coldest reliable temperature they could create in the lab at the time. This is where salting the roads stops working and also where you start to get black ice formation from exhaust condensation, so it's handy to know when you're driving in cold conditions.
32 and 212 (freezing and boiling points of water at standard (sea level) atmospheric pressure) is easy to remember - and the boiling point varies radically with altitude and barometric pressure so it makes little sense as a "magic number" for mnemonic purposes.
