It's all pretty basic stuff. Posted at same time as you, so didn't see the possible amusement factor, but he knows the answers anyway
Knot derives from chucking a wooden sea anchor overboard with a line attached, then timing the number of equidistant knots tied in the line that went overboard
One minute of latitude everywhere. It only goes "pear shaped" on a Mercator chart. A nautical mile is exactly the same the world over, or it was when I was in the Navy.