Misc: What is the distance between two rails on a track called?

Questions

In 1977 Groucho---------- , died in Los Angeles at the age of 86. ?

In 1977 Groucho Marx, died in Los Angeles at the age of---------- . ?

In 1778 ---------- O'Higgins, won independence for Chile, born. ?

In 1778 Bernardo---------- , won independence for Chile, born. ?

In 1860 ---------- Poincar, French prime minister (1912), president, born. ?