The president may love a juicy hamburger, but he can't love the price of ground beef heading into the midterm elections. California cattle rancher Megan Brown recently sold a bull at auction. By the time the bidding was over, she got more than she’d paid for the same animal six years earlier — a spectacular return on a bull that produced a lot of calves for her while in his prime. “It boggles my mind,” said Brown, a sixth-generation rancher north of Sacramento. “I don’t think that’s ever