"MARILYN MONROE: THE PASSION AND THE PARADOX." By Lois Banner. Bloomsbury. $30.Marilyn Monroe was Hollywood's archetypal dumb blonde. She was also one smart cookie.That's the twist in Lois Banner's richly researched biography "Marilyn: the Passion and the Paradox."The passion part is that Monroe worked tirelessly toward her goal: to become a movie star. Her name was Norma Jeane, but even her surname is the subject of debate. Her mother, Gladys Baker, was an independent woman from a Missouri family who moved to Los Angeles during the boom years of silent cinema and worked as a film editor. Her daughter, born in 1926, was given the last name Mortenson, after Gladys' estranged husband. Her real father was probably a polo player named Stan Gifford whom the girl spent a lifetime trying to find, literally as well as figuratively.