useless trivia: What Word Means: Four?

Questions

Who played the young Indy in Indiana Jones and the Last Crusade?

Which Spielberg movie featured the characters Sargeant Tree,Sitarski and Wild Bull Kelso?

Which film director, much admired by Spielberg,played the roles of a scientist in Close Encounters of the Third Kind?

Which of The Color Purples co producers also wrote the music for the film?

Who played the part of Elliotts sister Gertie in ET, The Extra-terrestrial?