Time Warner rejected 21st Century Fox’s initial stock-and-cash offer valued at $85 a share. The company wants the offer raised to above $100 a share, with a higher portion of cash than originally offered, according to a person close to Time Warner. Ever since his News Corp survived a bruising liquidity crisis in the early 1990s, Rupert Murdoch has been careful to avoid getting overextended financially. But his pursuit of Time Warner could test that philosophy