Track Star, Three OthersUSlt;irofTo StandTrial in SlayingLOS ANGELES (UPI)--Oneof the nation’s most promising high school track stars and three other youths have been ordered to stand trial June 7 for the March 20 gang slaying of a teen-ager.The lour pleaded innocentThursday to the charges stemming from the beating death of Robert Ballou, 16, who was attacked by a gang i when he refused to give up his leather jacket.d ««The defendants are Wash- Sington High School hurdler bRicardo Sims, 18, James Cun- vningham, 19, Judson D. Ba-cot, 22, and Bobby L. Clear, t,21. All are in custody without 0bond. dFour juveniles ranging in tage from 15 to 17 also were scharged in connection with pthe slaying, which occurred }outside the Hollywood Palla- -dium as the Los Angeles High -School football player left a irock concert . f