Cryptocurrency pop-answer: burn ROI and APR for LSDs

This LSD-problem is algebraic, so doesn't need to be solved in #Rust, but could be solved in, say, a ... SPREADSHEETSZORXEN!??!?

a) 10% ROI is computed by 0.9 * current exchange rate (10% burn rate column)

b) Since we have the burn period (unbound (days)), we have the burn APR