Treasury Secretary Jacob J. Lew has said the government will have only $30 billion of cash left by Oct. 17 to meet its commitments. Those can run as high as $60 billion a day, which means the Treasury will need to borrow more to meet its liabilities, Lew said. Goldman Sachs expects the Treasury’s cash balance to be depleted by Oct. 31 and “possibly quite a bit sooner,” analysts at the bank wrote in an Oct. 5 report.