Milestones

ARRESTED. Steven Wayne Benson, 34, ambitious, financially and maritally troubled heir to an estimated $10 million tobacco fortune; on charges that on July 9 he planted two pipe bombs in the family station wagon, killing his widowed mother and foster brother and seriously wounding his sister, after his much tried parent, discovering that he had apparently looted some $2 million from her investment account, threatened to cut him out of her will and the family enterprises; in Naples, Fla. Evidence linking him to the crime included his known familiarity with explosives and electronics and a latent fingerprint of his found on the remains of one of the bombs.