Meta Platforms Inc. posted sharply higher profit and revenue for its fourth quarter on Wednesday, thanks to higher ad revenue on its social media properties. Its shares shot up in after-hours trading even as it forecast increasing expenses on its artificial intelligence efforts. The Menlo Park, California-based company earned $20.83 billion, or $8.02 per share, in the October-December quarter. That’s up 49% from $14.02 billion, or $5.33 per share, in the same period a year earlier. Revenue grew 21% to $48.39 billion from $40.11 billion. Analysts, on average, were expecting earnings of $6.76 per share on revenue of $47 billion, according to a poll by FactSet.