Kurzgesagt made a fairly entertaining video about the effects of a supernova on Earth at different ranges:

https://youtu.be/q4DF3j4saCE?si=l-6wyBJo_Ouwq2wg

Lineages could claim copyright of children and their works as derivative. Entire families could claim copyright of their descendants and all works related. Each new generation resets the timer on expiration if the copyright expirations still apply.

Just pick up the fence and move it further north a few meters every year.

Anki is a FOSS flashcard program that is popular in language learning circles.