NEW YORK: Viacom Inc. says its first-quarter profit rose 33 percent on stronger results at its cable networks and the Paramount movie studio. Viacom said Friday it earned $270 million in the first three months of the year, up from $203 million in the same period a year ago. Per-share earnings rose to 42 cents versus 29 cents, or 44 cents excluding an investment write-down and restructuring charges. Analysts polled by Thomson Financial had forecast 41 cents a share. Revenues for the company headed by Sumner Redstone rose 15 percent to $3.12 billion from $2.72 billion. ap