On a proggy about rivers, boat could cruise at 9 knots/hour. Ignoring cruise, assuming fuel for 24h, how fast would it be going after 24h?
Some article I saw, can't unforget what, one nautical mile with metric in brackets: 1,9** (can't remember the last 2 figures). About 1,850m? Even 1,760 doesn't come to that - I did wonder if the author had used yards in a mile.