EVERETT - A Seattle man who hit a friend in the head with a football-sized rock and threw his body into Canyon Falls was sentenced yesterday to 30 years in prison.

Steven Henderson, 19, pleaded guilty last month in Snohomish County Superior Court to first-degree murder in the death of Don E. Hood on Feb. 1. Police did not hear about Hood's murder until 10 days later when a witness who was with the men at Canyon Falls came forward.

The three men had bought beer and parked near the water. Henderson, apparently upset about a remark Hood had made earlier about Henderson's mother, hit him in the head with a rock, dragged him to the falls and pushed him over. Hood fell on a ledge, and Henderson climbed down and pushed his body into the water, where he

drowned.