WASHINGTON (AP) a¿¿ The Federal Reserve on Thursday proposed that big banks keep enough cash, government bonds and other high-quality assets on hand to survive during a severe downturn on par with the 2008 financial crisis.The proposal subjects U.S. banks for the first time to so-called "liquidity" requirements, referring to the ability to access cash quickly. Fed Chairman Ben Bernanke said it would foster a more resilient and safer financial system, along with other reforms. ___ US unemployment aid applications drop to 350,000 WASHINGTON (AP) a¿¿ The number of people seeking U.S. unemployment benefits dropped 12,000 to a seasonally adjusted 350,000 last week, though the total was elevated for the third straight week by technical problems in California. The Labor Department said Thursday that the less volatile four-week average jumped by nearly 11,000 to 348,250. Weekly applications have been inflated for the past three weeks, largely because California has been processing a huge number of applications that were delayed because of a computer upgrade. The 16-day partial government shutdown has also lifted claims this month because a number of government contractors were laid off temporarily. A government spokesman said the backlog in California affected last week's figures but noted shutdown's impact appears to be fading. ___ Average US rate on 30-year mortgage at 4.13 pct. WASHINGTON (AP) a¿¿ Average U.S. rates on fixed mortgages dropped this week to their lowest levels in four months, a positive sign for the housing recovery. Mortgage buyer Freddie Mac says the average rate on the 30-year loan fell to 4.13 percent. That's down from 4.28 percent. The average on the 15-year fixed loan declined to 3.24 percent from 3.33 percent. Both averages are the lowest since June 20. Mortgage rates have been falling since September, when the Federal Reserve held off slowing its $85-billion-a-month in bond purchases. The bond buys are intended to keep longer-term interest rates low, including mortgage rates. And a slowdown in hiring in September makes it more likely that the Fed will continue its stimulus into next year.