useless trivia: What Word Means: A Sharp Edge?

Questions

In 1989 United Airlines 747 jet rips open in flight from ---------- to New Zealand, 9 passengers sucked out of plane, many injuries.?

In 1838 A London pedestrian walks 20 miles backward and 20 miles forward in ---------- hours.?

In 1841---------- , painter, born.?

In 1873 Enrico ---------- (in Italy), singer, born.?

In 1933 First aircraft carrier "---------- " launched.?