I've mentioned before that I've liked Susannah Nix's Chemistry Lessons romance series. Now the third title in the series,
Advanced Physical Chemistry, is free in both the US and UK.
Kindle US:
https://www.amazon.com/dp/B07958H7M8
Kobo US:
https://www.kobo.com/us/en/ebook/adv...ical-chemistry
Kindle UK:
https://www.amazon.co.uk/dp/B07958H7M8
probably also free at Kobo UK, but I don't check there...
There was an omnibus of the first three titles in this series on sale at good price a while back, but in this case, who cares - this single title is free, so you can get it just if you prefer having the individual titles. Or not!