Federal officials should consider reopening public access to about three dozen Web sites withdrawn from the Internet after the Sept. 11, 2001, attacks, a government-financed study says, because the sites pose little or no risk to homeland security. The Rand Corp. said the overwhelming majority of federal Web sites that reveal information about airports, power plants, military bases and other potential terrorist targets need not be censored because similar or better information is easily available elsewhere. Rand identified four Web pages that might merit the restrictions imposed after the attacks. 'It's a good time to take a closer look at the choices that they made at the time,' said John Baker, principal author of the study, which was funded by the National Geospatial-Intelligence Agency, the government's intelligence mapping agency. Advocates of open government said the report shows the Bush administration acted rashly after the suicide attacks when it scrubbed numerous government Web sites. About how many websites have been withdrawn from the internet after the Sept. 11, 2001 in America?