Made temperature readouts in line with the SI.

Made temperature readouts in line with the SI.

* The unit name 'kelvin' is written in lowercase, unless it starts a sentence. However, its plural 'kelvins' is more appropriate because of the context.
* Added a space between the number and the unit (e.g. 30 °C or 303 K).
* Wherever '°C' and 'kelvin' appeared in the same context, the latter is replaced with 'K'.

Ref.: *The International System of Units*, 9th edition (2019, updated 2022), Bureau International des Poids et Mesures