Warren Buffett’s Berkshire Hathaway reported strong first-quarter earnings as the conglomerate kicked off its annual shareholder conference. Omaha, Nebraska-based Berkshire added $21 billion in cash and Treasuries to its pile, bringing it to a record $189 billion last quarter — a 13% increase in just three months. Berkshire’s operating profit surged 39% to $11.22 billion from a year ago, thanks to a 185% year-over-year increase in insurance underwriting earnings — from $911 million to $2.6... Read this story