UnScramble this Word: e r t r t s a l?

Questions

In 1967 First Boeing ---------- rolls out.?

In 1983 Sixth Space Shuttle Mission - ---------- returns to Earth.?

In 1790 U.S. ---------- system established?

In 1864 Austrian Archduke ---------- became emperor of Mexico.?

In 1866 American Society for the Prevention of ---------- to Animals organized.?